Sorry, I can't help you with the manual. The owner's manual, especially from older RVs, really tell you nothing. I would suggest you make a list of all your components/appliances (i.e. refrigerator, AC, hot water heater, furnace, etc) and look for manuals for them. I think you will find they will give you much more info re parts, troubleshooting, etc.
Vera & Ken
1998 Holiday Rambler Imperial, RR8S Chassis
Cummins 6C8.3 mechanical engine, 325HP, 3060 Allison
Towing 2014 Ford Explorer