http://moellermarine.com/wp-content/uploads/2016/03/Open-Stock-Tank-List-with-Diagrams.pdf
MOE-FT4520 would be the closest size unfortunely I believe that if I raise the tank so the 65" would fit within the taper it might rub the top deck the overall height is 11.5" on the doghouse 10.5" on the ribs probably the most expensive tank I have seen though
^^^^The tank you noted, Moeller 4520, is not the correct shaped tank for your fuel coffin. It's listed as a "Rectangular Belly". This means the bottom of tank is curved. Your tank is rectangular vertical, essentially just a rectangle. Also, the 4520 tank at 9.5" high would be too high. You need to account for the height of the fuel inlet fitting plus the height of the fuel inlet tubing thickness. If I remember correctly, the top of my fuel inlet fitting was 1.5" and the fuel inlet tubing was 1/4". So if your tank height is 8", add 1.5" plus .25". That's 9.75" of total height, from bottom of tank to top of fuel inlet hose. Those fitting and hose measurements were for my tank, so don't rely on these numbers for yours.
You need to measure the height of the fuel inlet fitting (from top of tank to top of fitting) and measure the thickness of the fuel inlet hose before searching for a new tank. Also, what's your plan for installing tank? This will probably affect your search. For instance, when I installed my tank I used the pascoe method. This includes bonding 1/4" thick pvc board strips to the bottom of tank. So I had to account for the added 1/4" of height.
Whereabouts do you reside? I've got an aluminum fabricator to refer you to if you choose that route. He'll definitely be less expensive then other quotes you'll get.
