Needed to get my covers on my fuel senders managed...so.... 1) First I made a template with 5 equally spaced holes (used a template maker I found online). I taped it to the covers, marked the hole location onto the cover and drilled them. 2) Drilled the pilot holes on the leading edge skin. 3) Updrilled to #10 so I could use a nutplate 4) Hollowed out the cork behind the afformentioned nutplates. The bottom (front) one seems like it may rub on the tank therefore I ground it down by about a third. 5) Used my newly aquired nutplate drill guides from Osh this year. I needed to use a corner on due to it's proximity to the fuel sender wire in order to keep it clear. 6) Used my other newly aquired squeezer kit from Osh this year. Pressed on flush rivets (after dimpling first). FIN. Looks good. I'll probably still put a bit of a cork or rubber gasket under the cover. This will give it a little rise which should give the cover a wee bit of room over the sender cap.
Note: I got the Fuel Sender caps at Oshkosh from Kit Plane Enthusiast for about $15 though they are also here: https://kitplaneenthusiast.com/products/fuel-sender-fairing
