Must have had the fuel tank skin on and off 15 times today. Needed to drill the final holes in the spar/leading edge skins in this area, then deburr.
Cut the 4" hole in the skin for the access cover to the fuel sender. Then installed the access cover and used 3/32 countersunk solid rivets. The opening is 3" and the cover is positioned directly above the fuel sender so it can be removed if nesessary. Protected the wires coning out of the sender with a layer of shrink wrap and then plastic spiral wrap.
Enlarged the hole for the fuel filler neck so it would fit flush...quite a bit of material needs to be removed...essentially the hole ends up being about 3/16" smaller than the circumference of the filler neck.
The other thing I had to do to make the filler neck sit flush was raise the level of the skin on the downward slope side of the tank...I did this by doubling up the cork material in this area. Without doing this the neck sat flush on the leading edge side but about a 2mm gap was obvious on the trailing edge side. After installing the cork, the neck fit perfectly. I'm going to come up with a gasket or something to seal where the skin meets the filler neck...nothing silicone as paint will never adhere. Either a gasket or something like Permatex #2.
