-ok been reading up on as much as i can. have searched high and low lol.
here is what i have and what im looking to do.

-i have an 07 sierra classic rcsb 4.3 4l65 combo.

-I want to do a 5.3 or 6.0 swap, unless i find a 6.2/6l80 combo at an incredible deal.

- I don't plan on doing anything crazy just cam nitrous truck wanting around 500rwhp on the hose..

-What yr 5.3/6.0 would be the easiest swap to do?

-from what i have read I can reuse...
the trans.. correct? (i would deff go through it, hd2 kit and a converter)
pcm as long as i get it reflashed? correct?

now for the ?s..
-do i need just an engine harness or a body harness, i spoke to someone that said i need ed the whole truck harness replaced but that sounded ridiculous lol. so i hope i didn't buy the hardest yr model to swap if so ill sell it and start with another.

-will the 5.3 make 500rwhp on the bottle? (tunned obviously)

I have been in the Ford game for a while but this is my first gm "project" I have spent all kinds of cash building my lightning and can't see my self spending another 5-8k on another built engine.. The lightning was very quick but the time has come to join the dark side.. i heard theres cookies!