What type of manual are you looking for. To be honest, I've never seen what a manual from back then looks like, but Sunline never had a general manual for everything. I assume your looking for something like what you would get with a new car, that tells the details about everything. Your best option is to read the individual appliance manuals, and if your question is on something else, post it here! The only thing I can give you now is a link to the 1978 TT brochure and TT specifications:
(scroll down to the two brochures)
P.S. Love to see some pics!
2007 T-286SR Cherry/Granola, #6236, original owner, current mileage: 9467.8 (as of 5/26/19)
1997 T-2653 Blue Denim, #5471
1979 12 1/2' MC, Beige & Avocado, #4639
Past Sunlines: '97 T-2653 #5089, '94 T-2251, '86 T-1550, '94 T-2363, '98 T-270SR