The jacks on my Class A are.. Not well (one is missing in fact)
So I use a set of stair steps.. Now my wheels are 12" wide (22.5" XRV's) or close to it so I took 2x12
1' long
Two feet long
and finally 3 feet long
I made some of those just like you see the sentences layed out, Glue between the layers, set my car atop them for overnight (or the motor home) so they stick well,, NO NAIL OR SCREWS OR BOLTS.
and I made another pair
Two feet long
And finally 3 feet long
and finally somen "1'Long"
By mixing and matching I can get most any height I need to level.. Then I set pads down, use the one foot squares to build up a bit, lift about 2-3 inches with a 12 ton bottle jack and "Drop" (set gently) it down on jack stands.
Way better than the RV's jacks.