How do you beat the vehicles game

There is a video walkthrough at the related links, and the Hooda site.
The object of the game is to remove the dark (bad) vehicles from the screen, keep all the good vehicles, and get one or more of the good vehicles to the designated green Parking zones. The parking zones are not required to "beat" a level, but a certain score on each level awards a "star" and a player needs all 20 stars on the first 20 levels to play the levels from 21 to 35.

Here is the plan for each of the 35 levels. It may take practice to get the vehicles to perform properly. Click to start a vehicle and click again to stop it.
1. Accelerate the police car, but hit the brakes to stop it early, to land in the green space.
2. Drive the top car off, then ram the other one with the ambulance.
3. Drive the fire truck right, remove the striped area, drive it left until it hits the red button, then left to knock the SUV over the edge.
4. Remove the stripes to form the ramp, drive the police up to ram the SUV, then quickly back down to the parking space (need to get star).
5. Roll the fire truck forward close to the green zone, then race the police across the top to ram the SUV, then stop. Park the fire truck.
6. Full speed on the police, remove the stripe after the car passes, and don't stop until you're in the green.
7. Drive the upper left black car right to hit a glancing blow to the steel ramp. The other car runs into it, forming a ramp down to the SUV. Fire truck just sits.
8. Use the fire truck to push the ambulance backward, fully onto the stripe. Remove the stripe and drive the ambulance left to nudge the ramp. The tire rolls down and knocks away the black car. As the tire rolls, quickly remove the stripe and drive the police car to the park spot.
9. Drop the police car onto the fire truck and roll forward close to the ramp. Gun the police car to jump the ramp and hit the big tire. Quickly drive the ambulance right to park ahead of where the fire truck is going to fall, and the police car jumps back to land behind them. (Takes timing to get the 3000.)
10. Use the ambulance to push the steel beam to the left. Use the right fire truck to slide the other one left onto the stripe, and drop it onto the beam. The spinning tires will move the beam right and knock off the SUV. Drop the ambulance into the far left parking spot.

11. Start up the ambulance on the pole, then drive the other ones into the poles, stopping at the parking on the right. When the ambulance drives off the poles to the left, ram the SUV and stop at the other parking spot. (Takes some luck.)
12. Nudge the bar to lean in over as a ramp next to the black car. Push the fire truck into the ramp to knock away the black car, while gunning the police car to jump onto the ramp, to stop in the green space atop the small ledge. Definitely difficult to get the 1000 points.
13. Wait. When the fire truck catapults the SUV, quickly drive it right to park.
14. Turtle. Drive the fire truck directly under the crate, and remove the stripe. Gently drive the black car onto the top of the crate, and slowly cross to the left where the black car drives onto the other stripe. Drop the ambulance onto the crate, and take it right to the green spot before you drop the black car into the trash.
15. Jump the gap with the police car, ram the car and stop. Use the black car to push the crate into the hole, then ram him right with the ambulance, stopping in the green spot.
16. Drop the ambulance and use its wheels to send the beam right. When it drops and rams the SUV, stop in the green. Drop the fire truck, and use it to spin the beam back to the left. As soon as it is under the police car, drop the police and speed it left into the parking spot.
17. Drop the steel beam, and race the police car right to dislodge the tire. Quickly drop the beam the rest of the way down, where the tire knocks away the SUV.
18. Reverse course. Drive the ambulance left to the red button, then right to knock the SUV off before returning to park. The other ambulance does the same.
19. Race the police car, but hit the brakes when you reach the parking spot. The car should stop in time, knocking the crate into ONLY the top red button on the wall.
20. Drive the top ambulance right until it reverses, then drop the crate into its path. Drive left until the ambulance is on the first stripe and the crate on the one to its left. Drive the second ambulance left until it reverses. Drop the crate, then use the second ambulance to shove the SUV left, stopping in the right side parking space. Drop the first one into the left spot.

*You must have stars on all 20 levels to play levels 21-35. If necessary, use the level selector to go back and improve on your scores.

21. Ice. Little by little, edge down the slippery ice until you can nudge the SUV.
22. Shuffleboard. Hit the yellow bar hard enough to reach ONLY the first red button.
23. Stunt Driver. Edge forward to hit the red button. As the structure collapses, race the police car up the incline to fly across to the parking spot, upper right. (!)
24. Topsy Turvy. Flip the top two fire trucks upside down into the holes. The left one is easier to do. Then drop the beam on top of them. Ram the SUV onto the beam with the third truck, then spin the wheels to carry both vehicles to the right side. The SUV is easily shoved away, but it is almost impossible to get back to the parking space. Fortunately, a high score is not needed.
25. It takes both the ambulance and the fire truck to force the tire up the ramp. Once they are clear, use just the ambulance running to keep them there while you drop the other ambulance twice, reverse it to the left, and drop it again. Push the yellow bar clear of the slot. Then finish shoving the tire over and stop both vehicles at the top.
26. Drive the ambulance right until it reverses. Race the police car to the right, hitting the red button and coming back left to hit the SUV at upper left. Push the other SUV left with the ambulance, dropping the police car (or the SUV and police) to the parking at the bottom left. Shove the SUV left if necessary.
27. Drop the ambulance onto the fire truck, and drive right to hit the red button, then reverse, drive back across to the other red button on the left. Drive the police car right, then left to the button, then up the ramp to ram the SUV.
28. It all stacks up. You have to drive the police cars (a, b / c, d /e, f) into the red buttons in the proper order which is b) the upper level to the right, c) the middle level to the left. Now drive the bottom car left to get over the stripes. The next red buttons (e, f) are the two on the bottom level. The tricky part is that you then have to do the remaining cars (a, d) at the *same* time. Click the one at top level left and quickly the middle level right. All the cars will pancake and you can ram the SUV away.
29. Piggyback. Drive out the bottom fire truck and then the next on on top of it, to carry it to the level where it can hit the crate into the red button. The yellow pole will fall atop the fire truck, forming a ramp for the police car to jump and ram the SUV. Be ready to stop him in the green spot.
30. Power play. Race the police car to ram the yellow poles to the right, being sure to stop in the parking space. One should reach the horizontal pole and trigger the red button.

31. As soon as you start/stop the police car to get the tire rolling, get ready to race the ambulance onto the yellow pole to counterbalance the tire. The tire should knock away the SUV, leaving the ambulance (more than likely flipped over) in the green spot.
32. Drag race. Drive the top car right, then remove the stripe. When it jumps back to the left of the crate, stop it and ease them both out onto the striped bars. Start the lower police car racing madly back and forth, and on his third pass drop the crate in front of him so he knock it left. Let him continue to hit the crate another couple of times, then drop the other police car in his way. Eventually they will knock the crate into the red button, and you can stop him next to the other car in the green spot.
33. Drive the police car right, and leave the engine running so it will go under the yellow pole as you remove the left stripe. Drop the ambulance and drive it up the ramp to knock away the SUV, then turn back to reach the left but stop short of the red button. Remove the right stripe and knock away the black car with the police car. When the ambulance hits the red button, the yellow pole should fall right into place. It lets the lower police car cross to the left and knock the SUV there. You will have to hurry right to reach the green spot in time. But there is no score problem.
34. Balancing act. Slowly edge the police car close to the red button. Before you finally inch forward to hit it, park the front wheels of the ambulance on the upper left of the poles as a balance.
35. Spinning wheels. Inch the police car left into the hole so he flips upside down on the middle of the bottom. Use the black car to shove the tire on top of him. Run the police engine to spin the tire. When it is as fast as it gets, shove the crate over the edge with the ambulance, hoping that the crate will be tossed into the red button, knocking off the black car. Roll the ambulance on top of the tire to get the parking bonus.

*Alternate but tricky solution to 33 :
Remove the left stripe to form a ramp for the police car, but he will have to *pull a wheelie* to get up on it, driving up to smash the SUV at upper right before stopping. Drop the ambulance, but before you drive, inch the black car at the right forward a little so he contacts the yellow pole. This will prevent the ambulance from sliding the pole to the side. Now drive the ambulance across the pole to crash the black car away and stop. The police car reverses and heads back left, to stop in the green space as it hits the red button. The yellow pole should fall right into place to let the lower police car cross to the left and knock the SUV there.