Chevy 1 ton sport van, engine?

Hi, I am a huge car buff whether it be v-8's classics or imports. But my q is, if I can take the engine,tranny,rear end out of a chevy 1ton sport van and use it in another car. I would like to put it in a malibu but I might think about a rx7. I dont know everthing about chevy but I am assuming that it is a lt1, with a t400 tanny. It has a million miles on it but is rebuildable. I am getting the whole van for 300 bucks.