http://trailmanorrepair.blogspot.com/
I think MariaG has you on this one, she has a 1986 Trailmanor 25.
Our 1997 also had the side A/C, we took it out and put a microwave in instead. It doesn't get that hot here in CA where we like to camp, whether it be at the beach or the Sierras.
Welcome to the forum! It would be fun to see some pictures of those vintage TM's.