I repaired my tank with a sending unit block off plate, neoprene gasket, and sending unit bolts with the o-rings. All from Summit, tanksinc stuff I believe.
I drilled 5 bolt holes and made the hole big enough to put the bolts thru from the inside so the o-rings are inside and nuts outside. Cut groves in bolt ends to tighten with wrench and screwdriver.
They make a threaded ring if you wanted to slide that in the tank, and then bolts from the outside. I had a hard time lining up the ring once inside.
Tried everything else, nothing worked more than temporary.
I have a wagon, no new or used tanks out there.
Pic is test run with cork gasket and metal plate I made. Have since replaced with the parts listed above, no leaks.
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