Wiring harness help

[2drhoe]

Couple quick questions..
I am having trouble sorting through all of the crap when I search the glorious internet.

I am in between buying a harness and converting my existing one.
1998 4WD tahoe w/4l60e

I have heard that if I buy a harness I run the new ECU with harness for the motor, and leave my harness for ABS and such. Do I thin my original harness out of what I dont need?
Is there a write up for that?

Also if I convert my harness do I only need the new ECU or do I reflash my ECU?
Is there a writeup that you trust to be accurate for making my existing harness work for a Drive By Wire 5.3L. I think that is the route im going however I might go Drive By Cable.

[RPM Graphics]

i bought my harness for my swap from Nelson. a lot of people rework the factory harness but a new stand alone looks much cleaner IMO. i'm only using the LS1 ECU, i removed the factory ECU from the truck along with the ABS. i've heard of people pinning the LS ECU & keeping ABS & still removing the factory ECU.

if you look in my build thread i have wiring diagrams for 96-99. i sat down with the factory truck harness & the diagrams & removed everything i didn't need. it's not as difficult as it appears at first.