Thanks John & Mike! I did actually come across the LOA when researching prior to posting, but the oldest manual available was 1993. Given your advice, I just went ahead and started reading through the 93 manual & brochure, and it seems like it was likely similar enough to the 90 model to suite my needs.
I’m sure there are some slight differences, but in general it seemed to have the info I was looking for, and everything appeared in a similar manner as I’ve seen in my camper.
1990 Lance Squire 4000
2002 Ford F-250 7.3L