i don't have a chevy but will be getting a chevy engine but want to know size wise what the difference is. like whats the difference between the 350, LS7 and LS9 engines.

i've got a tiny truck and want to go nuts with it so it can't be TOO big thats why i'm keeping to the small blocks. i was looking at the LS7 till i realized the LS9 was smaller but a good bit more power

p.s. it's going in an '88 toyota pickup. i know i can get a 350 in with out doing any major changes, but not sure on the LS series