I recently removed all of the old foam out of my ThunderJet. It was easy to do, except for a few places that were hard to get to. I left all of the bow foam in, as that didn't look fun to get out. A question for you guys who have done this to your boats is, did you replace the foam, or did you leave it out? I'm afraid that if I leave it empty, the boat will be loud when I walk or drive in rough water. I also discovered that I might need to drill drain holes for water to be able to drain down into the bottom of the hull better. It seems water sits on channels with no where to escape to. The good news is that the foam that I removed was dry and there was no signs of pitting or corrosion to the aluminum hull. There was also no signs of broken welds to the support runners.