To add to this. After stuffing bags, sway bar and some home made stable loads under the back of my truck, it's getting pretty tight and cluttered under there.
You've got that stuff already plus the kelderman thing going on. Now add 2 more bags, 2 surge tanks and the associated plumbing, it's gonna look like the emissions system on a 1985 Cadillac. Hoses and hardware everywhere.
Maybe trying too hard for the unloaded Caddy ride and super conservative heavy load carrying capability.
With the rear air shackles, my vote is to add a leaf or 2, carry more weight where it was designed to go, thru the springs, and leave the parts bin full of stuff off the truck.
Qualified by the kelderman setup being stout enough to take on more load through the springs.