I really think this is a poor idea. I'm not trying to put anyone down but the idea of using a 3/4 ton truck to haul a liquid tank of any size is a little more than ridiculous in my opinion. The military did not make a tanker version of an M37 truck for the obvious reason that the tank would be so small it would not be useful. Same reason why they never made a M715, M880 or CUCV version of a tanker because 1 1/4 ton is still not enough to make it worthwhile.
This idea gets more foolish when you consider that for the price of a decent M37, you can buy an ex-firetruck deuce or 5 ton that is already set up with a tank or tanks for liquid. And while they will probably hold a lot more liquid than what the truck can handle, at least the drivetrain of a Deuce or 5 ton will take a bit more punishment than the comparatively weak M37 drivetrain.