Whats required to swap a 6.0 and 6l90 to an 01 silverado 1500?

[01silverado1500]

Hi all, I'm looking to swap a 6.0 and 6l90e from a 2012 4500 to my 01 1500. I've got a good deal on the motor, trans, ecm and wiring harness so i would like to swap my 4.3 and 4l60e with that. I'm just wondering what it would take to make that swap work. I know that the trans is bigger and would probably need a custom crossmember to mount it and a different drive shaft. My main concern would be all the wiring. especially to my dash and steering column but also what all would have to be custom fabbed to fit everything into the truck. Any info would be highly appreciated. 

[newdude]

I'd check out Custom ECM on Facebook.  They've done a bunch of 6L, 8L and are working on 10L swaps on that era truck, and others.