With my previous 5er I had the large bubble level on the hitch. Each big mark was 1". I stopped where she wanted the trailer, looked at level and told her how many boards and which side. I pulled up abt 10" and she placed the boards then I backed up, leveling done side to side. Placed the tire locks between the tires. Lowered front landing gear. Opened left font compartment door and placed a 2' level in the opening and adjusted front to back leaving slightly high in the front. Adjusted the rear stabilizer for F-B level and finished.
It goes without saying that the hitch level was adjusted when on a level slab and the compartment level was checked against the inside check points. Once verified never had to go in to check.