I did the same when we got our MH. I put a 12" torpedo level in the bottom of the fridge and fiddled with the levelling jacks until it was spot-on in both axes. I then attached two stick-on bubble levels, set to show level in each axis, near the driver's seat, where the leveller controls are.
Our leveller system has an auto function, but it really gets carried away and raises the rig to a ridiculous height. My procedure, with DW's help, is to lower the jacks until the pads just touch the ground. I then raise each pair as little as needed to get the rig level with the minimum of jack extension.
If I can't achieve level within my confort zone, I ask for another site or get a refund and go elsewhere. It has only happend once in three seasons and we got a better site.
Frank and Eileen
No longer RVers or FR owners