i have been doing a lot of research about this and really can not find a straight answer.

I have a 98 4X4 suburban with a 5.7 that i am swapping in a 6.0 from a 2001 4X4 2500. i have the complete wiring harness and computer. i have read 2 or 3 different things about this topic. i know i need to keep my stock pcm to controle the abs, a/c, air bags, and some guages. the gray area for me in the tranny and speed sensor wiring.
Do i keep the tranny and transfer case wiring intact from the 98 and use it? or do i use the 6.0 harness (the plugs look to be the same)? if i have to go this route do i have to tie into the factory 98 harness? if so how.

thanks in advance.