1982 18 Fisherman Fuel Tank Replacement

[rrichar1]

I am replacing the original fuel tank from a 1982 CC 18 Fisherman. I've included pictures and am having a custom made 25 gallon aluminum fuel tank created right now. It will cost roughly $325 and is being made in Houston Texas.

The questions/opinions I need are:

1. We cut the original in quarters (it had been leaking) and there were four main sections 2 in front and back where foam pads were that the original tank sat on. I don't want to put any new foam in but was planning on leaving the existing and setting the new tank on and strapping down with wood and straps. Opinions?
2. I accidentally cut two slices in the two pvc pipes running from the stern to bow for water drainage. Should I patch these or let them stay for water drainage of the gas tank coffin? Or should I add more drainage holes? The coffin is pretty water tight still.
3. In one picture I included I scraped away foam at the back going to the bilge area and had toyed with the idea of drilling through to allow water to run to the bilge. I know this could be an explosion hazard but would like opinions.
4. Four pictures: 1 is post cleanup/extraction. 2 is hole I cleared out going to stern next to bilge area. 3 is right front section that was resting on the foam that seemed to have the most corrosion. 4 was the bow portion of the tank after cutting top off and cutting it in half and removing stern section.

Thanks for any opinions.