Sweet 'Burb! A 2500 in good shape is a great find even if not perfect. I've got a 2011 1500 LTZ which has a suspension build sheet close to yours:
• Bilstein 5100 HD shocks (the front ones have adjustable spring perches which helped eliminate the need for a lift kit)
• Moog 1250 lb rear springs (which rid me of the blown air-ride suspension and increased the rear ride height about 1.5")
• 18" Silverado Z71 wheels and 275/65-18 General Grabber AT-Xs, which do rub ever so slightly
While the truck came with the HD towing package, I made one other major improvement since I bought it with a leaking radiator: I installed a 3" thick all-aluminum radiator with the integral transmission cooler. I'm only pulling about 4200 lbs with my 17' Winnebago trailer, but I can see some difference in the transmission temps with just this larger radiator. I'll probably install a larger external transmission fluid cooler to replace the stock HD cooler next spring. I also bought one of the Diable Sport AFM/DOD override plugs for the OBDII port so all 8 of the cylinders would fire all the time. So far, so good on that.
The rest of my build amounts to Weathertech mats, a good off-road GPS, maybe a roof rack for the trailer spare if the wife insists on using the trailer's back bumper for a rack to carry bikes on our trips, some way to carry some gas cans for remote parts of the SW, and an air compressor mounted in the primary battery location under the hood. Why the only battery is located in the secondary position on the passenger side is anyone's guess, but I'll take such small gifts.
Loving it so far, even with the 231,000 miles it had on it when I bought it. It was well maintained. And like you, I came from a Tahoe - the original 1995 four door version which I should have never sold. I was trying to tow the little Winnebago with a 2000 ZR-2 S10 but talk about under-powered, under-cooled, and under-braked... This truck makes all the difference in the world.
View attachment 260027