How do you nuclear bunker buster in mercenaries 2

Okay what you have to do is if you have it find it in your stockpile but if you already have equiped it open up your thing you call in like airstrikes and stuff for (oh boy this is going hard i play the computer one and know nothing about the Ps) and then find nuclear bunker buster then hold down laser thing then your jet pilot will drop it (you can get a jet pilot if you talk to Eva she will tell you about him then go follow your map to his garage) and if you don't have the nuclear bunker buster bought and you are not that far in the game then work your way up to the Chinese faction and i think you have to beat the faction (as in finish all contracts) but im not sure because i havent beeten it yet IMPORTANT!: IF YOU DONT KNOW ALREADY WHEN YOU GET TO THAT ONE LEVEL TO GO DESTROY SOLONOS WHEN YOU GET TO THE TOP OF THE HILL AND YOU DESTROY SAMS AND USED BNKER BUSTER (I MEAN THE ORIGINAL BUNKER BUSTER) WHO EVER YOUR BEING WILL MENTION SOMETHING ABOUT GETTING A NUKELEAR BUNKER BUSTER THAT DOES NOT MEAN YOUR GETING IT YET!