There are reasons why the water heaters are upright.
The cold pipe goes all the way down to the bottom.
The hot water goes to about the upper part of the tank to get the hotter water.
the consumable electrode ( corrosion protection) is placed in a way where the generated currents neutralize the greater majority of the wet surface of the tank.
The Heater locations to optimize the best heater arrangement for faster hotter water available.
SOLUTION: UP RIGHT AND WELL INSULATED to reduce the heat losses and in a crawling space, nothing is right.
Nando