Hey guys!
I just wanted to let everyone know that 15912581 is NOT the efan harness. It's actually the entire lamp harness MINUS the efan part, probably for the earlier trucks that do not have e-fans. I just bought it off of gmpartsdirect for the $109 price ($130 shipped), and now I will have to ebay it or something.
If anyone wants pics, I can put them up.
I think people are going with one of the original numbers, which was 15912597.
Just don't want anyone to make the same mistake I did!