You can either use large tapered door stops as in the pictures or cut some wood at the
angle then put duct tape or something over the wood to protect it from scratching the tank,
then lift against the belly tank. I use a 2x4 on the other lift arm as in the pictures.
a Belly Tank
|Large Door Chocks Installed on one one of
the jack arms.
|Door Chocks on one arm with 2x4 on other arm.