Lolliejack-
A Monaco Diplomat of that era would be a Class A coach, yet you posted this question on the Class C forum. Is your coach a Class A or a Class C?
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OK. more research turned up the following:
Manufacturer: Adventurer Manufacturing Limited Partnership
Web site:
http://www.amlrv.com/
Model: 2004 M-240DB (Class C)
This is a Canadian manufacturer.
I have no idea where to find a serial number. On U.S. coaches, there's usually a label near the driver's seat.
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