Fuel Cell Foam for a RF92 Van Diemen?

As you may know, the Van Diemen bladder doesn't have an access plate. The foam has deteriorated and I can't see any way to get it out unless there is a chemical that will dissolve it so it can be poured out ... and not also dissolve the bladder! I know the ethanol in the fuel will affect it but not enough to break it down enough to pour it out the fill neck.

I've got a nut ring and cover plate that I'm thinking about cutting into the bladder but I figure that ATL material is tough stuff to cut.

Anyone tackled this before?

Don

Fuel Cell Foam for a RF92 Van Diemen?