350 Holding tank leak
I have a 32 that needed a HT replacement a couple of years ago, but mine is under a port side cushion and accessible. First thing I'd do in your case is call IP; they may help with the costs. I think that by 2002 they had started using the epoxy coated tanks that are not supposed to corrode.
By 2002 the entire fleet had been complaining about the alum tank failure rate.
I strongly believe that plastic tanks are the way to go--no rust or corrosion. Look at Ocean Link in Portsmouth, RI; I think the link is oceanlink.com but don't really remember. They have hundreds of sizes and shapes at a lot less money than IP quoted me for another aluminum (uncoated) tank.
IP32 South Wind