Tank to wing leading edge gap

[TG777]

Plans say" The edges of the T-00001 Fuel Tank Skin must have a zero to 1/64 [0.4 mm] gap between the adjacent wing skin edges. A larger gap may be desireable if the aircraft is to be painted, while zero gap may be desireable if the aircraft is to be left in natural aluminum." Right now I have zero gap with a very tight fit and it looks great. What potential problems are there with leaving this a zero gap vs filing edges to make a gap for a painted wing. My concerns would be a lack of expansion space and its effect on cracking paint.

[Mark Browning]

My gap was zero both 14 wings and just shows how accurate these parts are made. I removed the tank and filed off a small amount for primer and paint.

The two RV-7's I have been involved with first my slow build and the quick build i have now haven't had any issues with paint cracking with expansion.
the gap is about the same i have on the 14 now.

[Reflex]

I removed the tank and filed off a small amount for primer and paint.

I did the same.

[rvbuilder2002]

This is mostly about easing removal of the tank if ever necessary.
Some paint shops put paint and clear coat on so thick that it can be difficult to remove the tank without damaging the paint.
With a gap, the paint can be more easily scored/cut if tank removal becomes necessary.