Aftermarket gas tank?

In my dart build, i cut the spare tire pan out, measured and found i can get a low profile, 25 gallon fuel cell rated for SCCA use from summit for about 200 bucks, with sending unit. Only thing I gotta figure out yet is how im connecting the filler tube.

Can you share the brand/model you found at Summit? I looked through a lot of them and wasn't sure which one you might be referring to. I picked up a '67 Dart project where the previous owner put in a drag race fuel cell. I'm interested in more capacity. Thanks!