Ask and you shall recieve! (Flip Top Gas cap Adapter)

Yeah it really depends on which cap you buy. I had a 4 hole pattern cap and it screwed together no problem. Only holes I had to drill were in the adapter. Id imagine that plenty of you have had to drill holes in the cap or the car, what ever you have chosen. Again, if I had to drill something, I think I would drill the cap base to match the filler tube pattern.