G A W W W D ! ! !
I thought about taking a look and then forgot! Loosing it.

In pic #162, what did you make of the 'cake' stuff between layers in the hole? Do I understand you foamed the void? To me it shows that the ballast has settled in the years since it was put in there with shop floor shims.

For anybody rennovating...
It obviously important to find out the condition of the ballast. In my considered opinion any void should be filled solid with something that will keep the space clear of water that seeps through the hull laminate and down through the bilge. And through the sump, if the boat has one like 338, at the end of the ballast.

It's possible, but nobody has reported it, that the ballast could work, move, as the boat is sailed. Even tho the area is supposedly sealed, my feeling was that if the boat went aground and holed herself down there at least it would be mostly solid stuff exposed in 338's case.