Drilled and clecoed doors to fuselage using rivet holes left open for the purpose.
Tried using the lines drawn to locate the holes, but this didn't work well. Also tried making a hole locator from two strips of aluminum but this also didn't work well. Found that by shining a bright flashlight through the holes from inside the fuselage the locations could be accurately located by the light showing through the fiberglass, allowing for accurate drilling to match the holes.
After attaching the doors to the fuselage with clecoes, used duct tape to tightly fasten the left door to the cabin top.