Welcome and congrats on your new to you Sunline! Your model number is a little short, it should be T-17xx. Either a T-1750 or T-1751 depending on the floorplan. Feel free to check out the files section of this site (tab up at the top) to view the original brochure for the trailer.
These trailers didn't come with owners manuals like a car does. In 1985, the owner's manual consisted of an orange binder that contained all the individual appliance manuals, as well as a generic RV operation manual, not specific to the trailer. If you're looking for wiring diagrams, plumbing diagrams, or anything like that, it doesn't exist. But, there are enough similarities between Sunlines that we can probably help you find what you need.
The generic operation manual, as well as quite a few appliance manuals, are also available in the files section.
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