I not-so-recently removed my headliner to track down a leak that was coming down my side pillars and soaking my seat belts... Long story short, don't cheap out on a roof rack, get a quality one like Sherpa or Prinsu, maybe even Victory 4X4.

Anyway - When I removed the headliner, there was obviously a snake of wiring for the dome lights all the way back and the wiring was stuck to the headliner with some black hard silicone material... What is this? I am finally in the process of needing to get the headliner back up there and reattach the pathway of wires to the headliner, but I already read that it's a big "no-no" to use hot glue, I don't think double sided tape will hold the wires to the headliner and all the silicone that I have seen is going to stay wet and tacky for hours...

Any Toyota techs happen to know - Or what have you done to resecure all the wiring when the headliner has been out?

I think your best bet is going to be the service manual. There are some copies floating around on the internet. I've got one somewhere, If I find it/ relevant pages Ill let you know