I thought the original interiors were more dingy yellow than the real life photos I've seen, where the interior of the conning tower and control room were usually painted off white. Also, I've always read that cork insulation was used (and it often rained cork during depth charge attacks). Here are some shots of the WIP new interiors for this mod.
Original look:
New look with white paint and insualtion:
With thanks to Digital Trucker for help finding the correct files!
I expect release of this mod in the next 7 days. Still a few things to iron out.