I made a drill guide from 1/4 inch aluminum tubing I got at the aviation department of the local hardware store. The walls were only 0.014 thick, but I found two smaller diameters that fit snugly inside each other for a three layer guide. Initially the outside tube would not slide into the bearing, so I removed a small amount of material with scotchbrite until it fit nicely into the bearing. Mounted the right elevator and secured the elevator "in trail" with a couple of clamps, then drilled the pilot hole. Removed the elevator and drilled the hole to final size. Deburred both sides of the hole. Repeated the process for the left elevator.