Traced all the wires from the ignition and the TIU and it looks like it's a deadend box just like the voltage regulator which I've already removed. Since all my wires are ready to go from the directions in the JTR book, I think it's safe to keep the TIU box out of the loop. Thanks for the help guys. Also, kudos to to a guy (wal280z) over on classiczcars.com who recreated the wiring diagram for a 77 280Z using autocad. I was able to print out a full size version in grayscale to have in front of me and also had the hires image in color on my screen to refer to. Made it a lot easier to follow. And full size means I had to tape together 12 pages of printout (49" across). Well worth the extra time to do that.