Bristol 42 trawler tank replacement

As a new owner of a Bristol 42 and 30 years experience in the Marine industry in both yacht repair and Salvage diving I'm reaching out to the Community to see if anybody has a sound idea for Bristol 42 fuel tank replacement I looked at the standard logical moller 115 gallon slanted tank that fits the dimensions in would have to do some modifications I'm just wondering if there's anybody out there that has had experience with plastic tanks and their trawlers and you can maybe give me a hint in which direction to look for not necessarily completely sold on having the diagonally slanted tanks that fit up against the hull would be open to more options like rectangular tanks on a Shelf just curious if anybody out there has made the conversion and has any ideas other than plastic I know all the values of stainless steel and aluminum just wondering if anybody is actually had any serious look with fiberglass I I'm a skilled fiberglass Tech as I mentioned before and have no problem making the laminations just looking for some designs and what people went through during the process of their build any things I should watch out for pitfalls or traps Etc any help would be much appreciated apologize for the typos big hands tiny phone punctuation Nazis give me a break

Plastic tanks are great , BUT require more time / effort to install.

Diesel will expand the tank , so it should be lightly mounted ,filled , allowed to expand , then properly installed

Foam in place plus physical mounting.

A couple of years ago Pro Boat Builder had a good article on tank mounting.

Sadly its hard to have a proper sump built into plastic , but a bottom drain might help.

Monel is as always the King of tanks , and worth the effort if the boat is a keeper, and you have the bucks.

GRP does work , but the tanks will need to be very stiff so sloshing will not allow movement / flexing of sidewalls which weakens them.

That is the single longest run-on sentence I have ever tried to read.

pete

I see you've just joined us..welcome aboard!

I'm guessing you're asking about fuel tanks, thought it best to ask:What will be stored in the tank(s)--fuel, water or waste?

If fuel, any plastic tank would have to be supplied by a mfr who makes USCG approved tanks. Neither metal nor FG fuel tanks are subject to any regulations.

--Peggie