First off, Welcome to Sunline Owners Club!
Now your door problem.
This thread may help on the rebuilding process. We have had many members rebuild their older camper doors.
I myself do not know on the older campers how the door hinges attach. On the newer campers, if you open the door and look in the hinge area, there are screws which hold the door unit to the hinge when is part of the metal door frame that is screwed to the camper wall. Taking those hinge screws out removes the door.
See if your 79 camper is made that way. If you get stuck still, take some pics of the hinge area and post them and we can see if we can help better. Someone with one of the older campers may be along shortly to help on how they removed their door or know where the screws are.
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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