Never said it couldn't be done. Its just going to be stupid expensive.
I bought a wrecked truck with a 6.0L engine and 4wd. It had a 6l90e transmission with transfer case. First off, the transfer case on the doner truck had the front differential on the driver's side, while my Canyon had it on the passenger side. I never got to the question if there was even room for a bigger tranny and T-case in the Canyon. So I saved myself a lot of work by sticking to the 4l60e and T-case. And I am going with the CCP wiring harness.Yes to wiring and Tcase won't bolt up at all. Need new front and rear driveshafts. Not worth the 6l90e hassle cause its a long pig.
I would be interested in what transfer case and parts were needed to "redesign" the 6L80 to fit the Canyon Colorado.It can be done. We helped a shop out in Tx do a V8 6L80 swap in an '05 Colorado 4x4 earlier this year. You lose your transfer case (it's too small and weak anyhow) and use another heavier duty GM transfer case. We just had to redesign our original adapter to reclock it to the GMT355 front shaft position. Everything else is pretty much the same as any 4x4 transmission swap.