Hey man, sweet rig...
Im in the process of building a truck very similar to yours right now from frame up! rockwells,divorced np205, SM420, beefy 350, the whole nine yards.. should be pretty bulletproof. Im putting a 12" lift in it with prolly like a 6 1/2 inch shackle w/ the shackle flip.
I want to run those same exact tires... ive been looking around and i found them at boyceequipment.com, is that where you got yours? how much did you pay for the tires and rims?
Again nice chevy!
Jake