There are two Rexhall groups that I know of. A Yahoo group and a private group. Can't recall the name of that one but it's likely a member of the Yahoo group can help. Another RV Forum, IRV2 also has a Rexhall owners group.
Agree with lou, not many owners manuals provide much information. Product info for appliances, jacks, mirrors, etc., are provided by the manufacture and not covered by the owners manual.