Being yours is a 85 camper, I'm making an assumption you have the combo, shower basin and toilet as an all one unit? It would help if we can see what you have now to help offer better suggestions.
We have had some members redo the walls with fiberglass panels out of the local lumber yards.
Here is one of the latest postings by KXracer704. He is restoring a Sunline a truck camper but it has a similar kind of shower/toilet. This may help you with some ideas.
He did his postings mainly in video. You may need to see a few before and after this one to get the total rebuild. He had to repair the basin first before building the shower surround. This link will drop you into post # 78 of his project. https://www.sunlineclub.com/forums/f...tml#post153913
Not sure what size space you have and how ripped apart the camper is, I have done shower surround changes in a 2004 T1950. The camper is bigger and the toilet separate, but they make pre-made shower basins and surrounds. Your camper being so small and a combo shower/toilet setup it may not work. This link will drop you into the shower stall rebuild on post # 59. It may give you some ideas to build on https://www.sunlineclub.com/forums/f...tml#post151304
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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