Although Zenith sells a composite cowling for the 601XL, they do not provide directions or suggestions for its installation. Therefore, some time was spent both in devising an approach, and making preparations.
1) Devised approach. A) The aircraft skin will extend 1.25 inches beyond the firewall. B) A .040 6061T6 spacer will be added inside the skin beyound the firewall, cut flush with the existing skin. C) A .040 6061T6 mounting surface will be installed inside this. D) The cowling will be attached to this second surface with MS21075L3 nut plates or equivalent. 2) Fabricated tool to locate 1.25 dimension on aircraft skin. 3) Cut aircraft skin back to 1.25 dimension. 4) Drilled holes for spaces and mouning surface. 5) Drilled spacers & clecoed in place.
