Please don't take this the wrong way. I'm not casting aspersions on you but, judging from the way you asked your questions, my feeling is that you're way over your head in a project like that. I think the idea is cool and would love to see something done like that if done well. I just can't see it as a garage project. Regardless, WTH, if you got the ambition and skills, go for it.
FWIW, I can't see anyone w/o connections scoring a Viper drivetrain for 1/2 the price of a new gen HEMI. A Hemi out of a low mileage truck are around 1500 bucks around here.