Looks like I used the ls plug on the alt. Then run a large gauge wire from the stud to a junction block on the firewall on the passenger side that I added. It's from the 07. Which is then tied into the small junction block on the driver side firewall (factory on your truck). You should be able to trace the wires back on that plug. One of them should go back to the little junction block on the firewall. Trying to remember but I think one went down to the starter and maybe the battery. You should not need the old alt. plug. So all you need to be sure you do is tie into the one that feed 12 volts (hot wire) back to the block. I my have a few pic of how I did it if you need them.
Eh, that is mildly confusing but I think I got it. Just snip the brown wire from the alt plug and then snip the split off from the alt lug and run the main fuseable wire with the circle termial to any 12v battery wire spot.

I wanted to use just 2 harded washers or a solid spacer but ace didnt have enough of the thicker solid washers and I didnt know where to get a spacer.
now it just needs an air intake hose, coolant, exhaust finished, and vss sensor wired up.