I installed the roadmaster air brake system on my 1999 Monaco Dip and on our current coach. The Monaco didn't have an unused port on the brake relay so I had to use a tee. Roadmaster wanted $35.00 so I went to a shop in Olympia and got one for $10.00. Our H.R. Scepter had an unused port and was a snap.
Air brake system works great, as some others have done I attached the (emergency) air cylinder to the brake piston as there was not much room for it under the hood of our toad. When the brake comes out of the toad for driving, so does the air cylinder.
John and Cherrie
2003 Holiday Rambler Scepter 40DST
Pushed By 2003 Ford Explorer