We overfilled our forward water tank and it started leaking from the inspection port.
This is a job which is relatively easy to fix and yet the results (if left uncorrected) may quite likely destroy a good portion of the water tank supports. I don't see how you can live with something like this.
#1 job is to make the inspection port 100# sealable when closed. Even with a head of 1 -2 feet of water on top of it. If you don't do that, don't waste any further time on this problem.
Does anyone see an issue with drilling a hole in the bottom so it drains to the bilge if this happens again?
Just a waste of time and the surrounding wood will eventually rot because you cannot get the drain hole down to floor level and the boat never sits exactly horizontal.
I had to use a sponge to get it out.
If that gets the most water out, do that EVERY time it overflows and hope for the best as far as rot goes.
Please read reply #5 over and over a few times and it will eventually hit you. The problem is that you're standing way too close to the problem and by now, you're eyes are probably exhausted.
While you're down there, send a few (more than one) pictures of the inspection port. Sounds like you've got the same setup as I do and I can't make mine leak even with a two foot head up to the overflow drain.