Concerning the Ford F53 chassis ride height, measured from the frame to the ground or from the frame to axle is going to change with each make and model of coach based on the weight of the house built on it. Coach loading by the owner will further change the measurements. Ford never produced the chassis with an independent front axle and never included any means to adjust the ride height to compensate for loading.
There are aftermarket suspension modification kits available that can run from a few hundred to several thousand dollars. If you have the budget -
Kelderman Air Bag Suspension