since its been done on the half ton's what about the big boys?

my 07 2500 suburban has a 4L80 and of course a member bout an hour and a half away has a 6L90 I'm debating trying to use.

I was told the 4L80 has a seperate TCU, and that the 6L90 has one inside the unit in the pan? The 6L90 would come with harness as well for a LY6 and of course thats what I have now. I'm just hoping this doesn't involve a ton of downtime, and its a fairly straight forward swap.

If needs be I have access to EFI live and tech 2's to make things doable.