Hi Kevin,
Its real simple if you keep everything orderly, pre plan, make and keep good notes.
Drawing a layout will help you with this. I like to go by systems. Each has a separate harness. It makes it easy when you have to troubleshoot it later.
Engine (PSI)
-Fuel delivery system (fuel pump relay, fuel pump controller if applicable)
-AC/Heating (Vintage air)
-Lighting (front and rear)
-Electric windows
-Power locks
-Alarm system
On the engine side of the AAW harness you can remove the:
-alternator/regulator wires 1 18g brown wire
-ignition coil wires 14g pink
-blower circuit wire (remove when using vintage air) 10g orange reroute inside to feed Vintage air blower 10g red.
-tachometer wire 16g white wire (redundant from PSI harness)
-oil wire 18g blue wire
OR leave in and use for Vintage air comp wire via safety switch (VHX and PSI use own)
-coolant temp 18g green wire
OR leave in and use for Vintage air heater control wire (VHX and PSI use own)
With the PSI harness you can tie into the back of the fuse box using the circuits you just deleted. Keep in mind what you will need while deleting circuits. LS1/T56 DBW 1017 instructions here:
http://psiconversion.com/tech_articl...structions.pdf
-Constant battery 12V
-Ignition feed 12V key on
-Tach feed
-cooling fan 1
-cooling fan 2
-brake signal.... note: I had to run a dual circuit switch due to the alarm system we used. The PCM had a 3 volt feed back and it played havoc with the alarm/push button start system.
The nice thing about the AAW harness is it has an additional connector with all the main feeds to run accessories. I have found that I didn't need it but it was nice to have.
Before you cut into anything. READ the instructions, plan it out and lay the harnesses out to familiar yourself with the two. I go as far as labeling each wire and what what it will tie into on both ends.
Make sure you make a note of these in the instructions. And don't get frustrated if you find yourself doing something over and over. It usually takes me 3-4 mock ups just to get it right.