I am using an in-bed fuel filler due to my paint being several years away from being re-done. I planned on going the boat deck filler route as I have seen, but my Boyd's Welding tank filler neck would need to be cut and welded with 2" pipe to accept the boat neck.
Has anyone ever carefully cut the bed floor and actually used it as the hinged piece? I think it might actually look cleaner than the boat filler. Of course I wouldnt be able to load it heavilly in that spot, but my truck's work duties have pretty much been retired anyway. Some spot welded 1/8" flat bar should give it enough support.
This is a rough napkin sketch of the concept