I have the same year Sunnybrook Titan trailer as you do, except that mine is a travel trailer and not a 5th wheel.
The Sunnybrook Titans all had walk on roofs and you can get up there (carefully of course) and do what needs doing. I, until lately, have been on my roof many times for cleaning, maintenance, and even air conditioner work. I am not a small person but the roof had no problems holding my weight.
It has been an excellent trailer for all these years and still gives us much enjoyment and pleasure. The Titan was Sunnybooks top of the line unit and was built much better than many of the trailers being built today. I go to the RV shows every year but have never found anything lately that comes up to the quality of the Sunnybrook.
I just replaced my Dometic 15000 btu unit two years ago because the fan motor required my getting on the roof every time the air conditioner was started after a period of non use to turn it and free it up. Looked like a somewhat major job to replace the motor so I replaced it with an
Atwood "Air Command" 15000btu unit with a heat pump. I have been very pleased with the performance of the new unit.
Enjoy your Sunnybook. Take care of it and it will give you many more years of comfortable service. :)
Barney