Switching from 2V to 4V

Hey guy's, I had a confusing question. I currently have a 2001 GT that is bone stock all the way down to the exhaust. My question is this. I am in love with the Terminator Cobra's, but because of my going to school I can't afford one. Would it be possible to change out the internals, heads, and anything else to match that of the 03-04 Cobra? I'm all for saving up for parts and switching them out little by little. Would it be easier to just buy an 03 Cobra crate motor and drop it into the body? If so, where could I find one? I would appreciate any help and info. Thanks! I'd like to make my car a sleeper to beat the crap out of this little SRT4 that keeps bugging me to race him.

Mach 1 4V motor

Where can I find that Mach 1 4V motor?