When I did my 99 Ford Mountain Aire the rear passenger duels would scuff the top of wheel well when coach rocked to pass side.
Dealer said he could not do job air bag bracket couldn't be mounted so I did the job myself, I was younger than.
Don't know why they said to raise rails in pairs. Should be the rear pair and front pair.
I had air valves that would allow more air into the one that needed to be raise more which was the passenger rear duel. When both rears were raised it would level the whole rear of motor home.
The front bags I fed air to balance with the rears.
It improved the handling of coach.
I had a other coach Ford that I had leaf springs added by a reliable spring company on 98 coach and they raise the coach 3" all around with different size springs to level.
With the bags I had control and could compensate for the different weights mostly in rear due to fuel and holding tanks adding or deleting the fluids.
The front bags were at the same air pressure most of the time.
Controls for rear bags was mounted on my dash so I could control and front bag control was in a basement compartment with compressor and valve air control relays.
The
AIR-LIFT Systems now have I understand auto controls to compensate for differences in weight shifts.
Just notice they have a wireless control now also.
I would shift your air lines as you said, rears pair both controlled and front pair controlled together as pairs.
Also there were no shims place under axels or springs in either the spring job or air bag job I did, some outfits would do that.