Levelling blocks for camper on driveway with 2 degree grade

Threaded rods against the grain !! Absolute genius !! Come spring I will be making my own.

You say you don't have a truck.
That means the camper will be resting on the jacks, right?
Why do you need blocks? Use the jacks to level it.

However, it would make sense to put supports under the camper floor to eliminate sway as well as the side loads introduced to the jacks by being parked on a non-level surface. This will take a lot of stress out of the jack mounts.

Edited to add: of course the jacks need to rest on solid, firm ground. You can put pieces of wood underneath to distribute the load.

Even if it there were not needed for the driveway, you will need them for campgrounds where the camp area is not perfectly level and flat.

You can buy a box of RV leveling blocks but they will be plastic and can easily break. I was able to find some scrap 2x8 boards and made my own. I cut them about 1' long, beveled one side and reinforced the wood with threaded rods across the grain. They have held up for many hundreds of uses. I frequently need to stack them 2 or sometimes 3 layers high so I carry 6 blocks. On occasion I have used them all but never needed more.

The camper jacks are adjustable. Or I’m not understanding the question.