Earlier this year, had the rear upgraded from a 2.73 open diff to a 3.73 TruTrac.
As of this weekend, we've got a new heart being prepped to go in.
2001 (or 02) 5.3 LM7. Supposedly around 120k, found on FB marketplace from a local guy who sells a lot of copart/junkyard partouts. Also picked up a 2wd 4L60E at the same time. I know they don't have the greatest reputation, but I'm not planning on racing or beating on it, just driving and light towing (~3k lbs). So we'll see how long it lasts.
Plans are to leave it stock for now, just clean it up a bit. Going to attempt my own harness and thinking of getting hptuners to try and do the basic unlock/etc myself. I'm a nerd and tinkering/being able to make my own adjustments is really appealing.