as the tittle says is there any problems i should know about or worry about and what trans should i run the 4l80e that i got with the eng or the 4l60e that came with the truck the truck is a 94 ext cab 4.3 the 6.0 is a 2000 i plane to change cam, heads intake and injectors from an ls6 and getting the wiring harness from current performance am i doing it right so far anything else will help

 

Just put it in, wire it up and make it work. That Trans will be snug in the tunnel..