I'll help you out a little- The numbers/pins for RadioShack Relay# 275-218.
Remember the wires on the ECU side of the cut should be dangling, except for the violet wire that just gets tapped. The violet wire is the power wire for the 4WD ECU, so juice still needs to flow through it.
Did this mod today and it works great. Quick and easy to setup, I just have to go back and clean it all up and make it look pretty now that I know it works. Thanks so much tacosupreme and all ya'll that took the time to figure this out and post it.
I did the gray wire mod on my 06 taco today. Everything went together easily. I tested the locker and it engaged great. I went to disengage it and the light wouldn't shut off. Then I realized it wasn't disengaging. Would this have to do with having a latching relay instead of the non-latching relay it asks for? The people at RadioShack new nothing! Please help!
Thought this was going to be an easy trick but alas no. I guess someone at Toyota had the grand idea to change things around behind the glove box. The 4x4 CPU on my 2013 is tucked up tight against the airbag and mounted to a bracket with a very hard to reach bolt. And the wiring seems different. (yes, I am sure I am looking at the 4x4 CPU!)
If there has been an success with this mod on a 2012+ truck please let me know!!