60 gallon gas tank

Figure out what brand of tank you want. There are only a few and I doubt any of them make a 60 gallon tank that is a replacement for the original. You will have to get a tank that goes in the bed to get one that big. On the manufactures web site they usually have a list of installers.

Will it hang under or are you considering a tank in the bed ? When talking to installers say " diesel " , many will not work on gas .