Fixing a previous owners really crummy patch

I thought this procedure might help someone else with a leak, or unlucky enough to punch a small hole in their hull.
All season my /cat was taking on water in the right hull. After 5 days of sitting in the water & sailing I would get 5-6 gallons out of the hull.
I finally put the Cat on my powerboat lift, slightly pressurized it while kids sprayed soapy water over the hull. I found the leak pronto, a thumb sized hole below the waterline that had been very poorly patched.
If you don't have ports, or can't reach the area from existing ports, it is difficult to add layers from the inside. You can add all the layers from the outside, but that tends to build up above the level of existing gelcoat. If they are inside, they are out of sight.
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