you can do what I did. I had an 1985 13.5ft and our water heater started to leak. After our last trip I pulled out the heater (took my sweet time). Unwrapped the insulation. I lightly sanded down the aluminum surrounding the leak with a "finer" sand paper.
Then I applied a fiberglass mixture, same stuff used for automotive use.
You should overlap at the very least 30% to 50% of the area that appears rotted. Let that fix cure for slightly longer than recommended. Then, before reinstalling the tank, fill it with water, slosh it around until you're satisfied that it does not leak.
This way you keep thing factory and original. I think my repair cost $20.00 ???
Hope that helps
Jerry & Debbie
Ford Explorer 4.6 Triton V8, AWD, 4x4
1985 Sunline Saturn T-1350
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