Blazer tank vents and fuel neck?

[muddpile]

On my blazer tank, there are two vents:
-One goes to the carbon canister, which I don't have so I'll just use an ATV tank vent.
-One goes to the fuel neck, which I have not designed yet.

My question is, what is everybody doing for fuel fillers through the bed floor? I've seen lots of people use those billet looking fuel doors like everyone bolts to newer trucks, but what do they use for a cap/neck setup under that, and can it be filled reasonably quickly?

Also, I doubt my gas cap will be vented, and neither will my fuel neck, so should I just run two of those ATV vents instead, or is there a better way? Thanks!