The Manufacturer or a dealer would have these. But didn't they go out of business? I can't keep up anymore. If you can't find a dealer or someone that got them from the manufacturer your probably out of luck. Those drawings were kept by model number at the factory and usually discarded after 5-7 years.
Mignuts, welcome to the forum. I was able to get wiring and water line diagrams from Winnebago for my ole 89 Chieftain. They emailed them to me via a file attached. Was great and great service. I've sent many emails to them and they have never let me down. Like S.Harrington said, if manufacturer is out of business, you might hae troble. Good luck :laugh: