I don't think I did anything with them.... I believe I just removed them from the 5th platform and bolted them to the chassis. I will have to check for you.
My knowledge base of air brakes is minimal and I wasn't sure if they could just be deleted and capped, so I left them alone. I did that with the intent of going back and cleaning them up eventually though but I am wanting to get the camper useable first. I have a hatch in the floor over the trans where they are and should be able to access from the top and bottom as needed.