GMC Gas Cap

A mechanic quoted me $375 for the small spring loaded cap that "seals" the gas tank. That was an insane number for something so small. So here is my solution. I took measurments with my caliper and came up with this. its .5mm larger than the outer ring but with the shrinkage factor it is a snug fit which is what I was going for. This is my first time designing something hopefully this helps just one person and ill be happy.