Unless you are planning to eliminate the foam and now have a way for the water to exit the tank compartment, I would not suggest that. Plus, are you getting the tank epoxy coated? If you are, you should be fine leaving ell enough alone.I was discussing tank replacement with a boat dealer in my area (he was also a Parker dealer). His suggestion to reduce corrosion of the fuel tank was "you should periodically take a water hose and wash the tank down to remove/reduce the salt build up which causes the electrolysis/corrosion". I have a 2300T and it has a pie plate over the tank sending unit so the idea was to remove the plate and stick a water hose in there, let it run for a while, and the water will all "drain out the bilge while removing a lot of the salt build up".
Anyone ever heard of or tried this?