More work on elevator, which is more delicate and complicated than I expected. Ordered a pneumatic angle drill because of tight quarters drilling so I can avoid drilling errors / damage to parts with drills that are too big. Ran into an issue with the CH750 prefab tip ribs not fitting correctly with the trim tab channel ends, which are slightly bent to accommodate fitting inside the tip rib flanges. Aligning the center of the trim tab channel flange properly with the third hole in the tip rib causes the tip rib flange to bulge considerably. So I have a technical question submitted to Zenith about it.