I am not 100% positive what they did back in 1985, however green is the standard wire color for the hot wire (+12VDC) on the clearance lights. And Sunline did use white wire on the year 2000 campers for DC ground (-12VDC)
Does your main battery cables have a white for DC ground? They would of kept the same method throughout the camper.
If you pull the right side (the door side) rear stop light lens off, you should see white as the bulb outside casing of the bulb holder for ground. Green and Brown would be on the center stem of the bulb socket. Again in the year 200 models at least.
Hope this helps
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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