filler neck modification

I keep forgetting to post pics of the one I got from Layson's. It's really nice, and I like that they include a rubber plug with a twist lock, and the cup still allows for the vent tube to function easily. It's really well made, but it's definitely not cheap. If you are a good fabricator and can do it yourself with a welder, go for it. If you aren't, or don't have the time, this is an excellent alternative, and I'm very happy with the finished product.

The plug is an extra nice touch. It means 0 fuel escapage on hard cornering, which is great for a street/autocross car like mine.