After a full day of gardening & another doing yet another simulator, today I was able to get back to the wing tips. I completed the left wing wiring support as per the right wing then fitted the left tip to the upper wing surface. The tips both needed a lot of cleaning up around the mounting flanges, lots of ridges in the 'glass didn't allow them to sit cleanly inside the skins so I spent a few hours with a file & sanding block trying to improve things. Mike Blythe told me the tips are designed to be fitted in a way that the top surface is flush & parallel, span wise, to the top surface of the wing at the main spar. Unfortunately, my tips are not flat on top so I have simply placed a digital level across both of them at the same position & set the tips at the same angle. They both indicate + 0.6 degrees.