Your 1985 T-1660 does show up in the 1985 brochure in our files section. There is some good info in the brochure on all of the 85 campers.
In case you did not know about our FILES section, see here for how to get to it.
To get to the FILES section, you have to be logged in. Look up top along the forum for the words "FILES." That is a tab; click it. Then select the area you want to go to and can read on for hours, days, maybe even weeks...
See the brochure section, then scroll to 1985 and download a copy.
As to how many T1660s were made in that year and what number yours was in the build quantity, that is a tough question to answer with Sunline now not in business. Member Sunline Fan may have some more insight on this; he is our resident older Sunline camper guru, but the exact number of T-1660s made may not be known.
I hope this helps a little.
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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