1977 midland under deck fuel tank placement?

Looking for help in determining the best place to put a below deck fuel tank on my 1977 midland 19’ skiff.

 

In a 19’ skiff, built in fuel tank placement options are pretty limited.
Where was the original tank, and why do you want to mov it?
Most boats in this size mount tanks under the deck, and not too far forward so as not to negatively affect the trim.
How much tankage do you need?
I would keep it minimal, so that it is not carrying a large weight penalty, which leads to more fuel being burned.
This is obviously a day boat, so it only needs to carry what you normally consume in a day, with some reserve.

 

I carry 19 gallons now above deck and in console of center console. Problem is it gets bow heavy and center of gravity is off. I had purchased a moeller 25gal. Tank that im gonna run on deck little under console and extending under cooler seat and ill make a cove around the tank and glass it in. I have a heavy t top on the boat and feel i need some ballast as well, so maybe the tank being 47L18w7.5h would help create ballast. Seems boat is top heavy. I run a 2015 etec 90hp, pushes boat 22knots, rebuilt floor and stringers already. Day fishing trips are usually 10 to 40 miles per trip. Long Island sound, block island, new york, rhode island.