I have had quite a few toy hauler RVs, both class C and Class A. Currently I have a Class C 31C FunMover and I have a Class A Thor Outlaw which is a 37MD. The interiors are pretty much bang on 8-feet wide. The Garage area in most that I have had are 10-feet long, but I had one that was 8-feet long and one that was 14-feet long.
I am not sure if that is exactly what you are looking for. I can email you my floor plans for each coach if you wish. Just private message me your email address if you want. or of course you could ask more question on here.
Jay and Cindy, 2013 Thor Outlaw 37MD (up in smoke and fire).