Um, obviously you haven't done lifters on an LS motor.... You need to pull the heads to change the lifters. It's not like the old 350. This is a fairly involved job...Run it and when the lifters start shitting themselves just pull the intake and replace them with LS7 lifters. It's not that bad of a job. Might as well keep the gas mileage while you can, disabling it doesn't seem to make the lifters last any longer as far as I can tell. I've flashed a lot out with HPTuners. I kept them on my L86, even after the VLOM failed I put factory lifters back in with a new VLOM and kept using AFM. It's nice to get 30+mpg around town.
A Prodigy brake controller, a set of decent tires (2800lb+ Pmetric or LRE), a Hellwig 7800 rear sway bar, and Firestone Sport-Rite 2320 airbags... and it will be way more nice to tow with yet still get better gas mileage and ride better than a 3/4 ton. You can drill and tap the frame for the bag brackets. I've put the same setups on 3 of my trucks and 3 other trucks ranging from 1999-2018. Well, except my last two trucks came with integrated brake controllers.