On this thread...Tom 417 states he has a TM23 and he is still a site sponsor so perhaps you could pm him:
http://www.trailmanorowners.com/foru...ight=1990+TM23
I found this using the search button and typing in TM23.
He also says that the floor plan of him TM23 is basically a 2720.
I gave you a link to an on line manual for TM's. The bathroom is always in the same place...the models of the converters, air conditioners, stove, heater and refridgerator do change over the years. You can usually find the on line manual for most appliances on line by googling.
The are many links on small rehab projects...constantly discussed on the forum...for instance curtains, recovering sofa, installing pergo type flooring or vinyl flooring...the a.c. is sometimes discussed as well. Older units btw I believe used a window unit mounted on the side of the camper.
Have you picked up your TM yet? Can you post photos?