Atlantic British Ltd. - Largest Independent Supplier of Parts & Accessories for Land Rovers

Place neoprene on all mounting brackets of ladder.

Once neoprene is in place, place ladder on the door making sure ladder is lined up with the line of the door.

Mark placement for drill holes at ladder mounting points and place ladder aside. Use 11/64" metal drill bit to drill pilot holes for screws at the marked points.

Align ladder back in place and secure it on top with one screw. Step away and make sure ladder is still lined up. Once you are sure the ladder is lined up secure the ladder at the bottom with one screw. 

At this point the ladder should be completely lined up and ready to be completely screwed into the vehicle to finish installation.