You can try the Ford Motorhome Assist Hotline at 800-444-3311 but I believe the answer will be "buy a service manual". The chassis manufacturers do not provide service documents with every chassis - just an owner manual with basic operation information for the chassis driver controls, fuse locations, etc. It's the same as with a car - you don't get service documents with them either.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL