2000 Chevy Silverado Engine Swap

The vehicle is a 2000 Silverado Z71, with a 4.8L and a 4L60E. I want to drop at least a 5.7L into it, hopefully a 6.0L.

Just wondering how simple or complex a swap is with an electronic engine is. First off, can the 4L60E handle a 6.0L or even a 5.7L? Or should I get my hands on a 4L80E.

Also, is it a simple matter of swapping the motor and computers, or are extensive modifications required? I would assume all the mounts and vehicle harnesses are the same if the motors I'm interested in are factory options.. Thanks for any and all info.    

As far as I know, most of the Gen-III and IV small-blocks are relatively interchangeable. You should be able to drop in a 6.0 Vortec pretty easily. I'd check out:

http://www.turnkeyenginesupply.com/index.html

They're kind of the authority on engine swaps. I'm sure if you check out any GM-specific truck forums, there will be some guys that could give you some pointers on doing a swap like this. I found this discussion thread that might offer some helpful tips:

http://forum.ls1truck.com/lofiversion/index.php/f6.html  

I was shopping around and discovered an late model 8.1L Vortec.. Any idea on interchanging a small block with a big block?    

You'd definitely have to upgrade to the 4L80 for that, but anything is possible with enough time & money.    

help!!!!!!!!!! I have  99 chevy 1500 4X4 5.3 with a busted tranny. I have a wrecked 99 2500 4X4 with a 6.0. I believe one has a 4L60e and the other is a 4L80e....my question is can I stab the 4L80 in to the 5.3 with out rewiring the truck or swapping out any electronics? Any help would be greatfull!  

If the bellhousing pattern is the same, it should be no problem. Generally, swapping the engine & trans together makes for the smoothest swap, but you could probably do them separately. What MY is the 6.0?