Here is a link to FMC motor homes. They are all 29 ft long with a rear engine. Originally they were all Chrysler 440's, but a number have been converted to diesel. If you are going to tow, a diesel would be preferred but a number tow with the original 440.
FMC photo albums by BigRabbitManBring up BigRabbitMan's photo albums (that's me) and look for the various Rally photo albums to see a number of them. The roof and wall down to the beltline is all one piece of 1/4 inch fiberglass. Nothing is laminated nor are there any wall or front cap seams. I like mine, but it may be too small for you. I have put 75,000+ miles on mine over 15 years. I did upgrade it to a diesel 25,000 miles ago. PM me if you want more info as to floor plans etc.