[swamp rat]

I see you allready installed a flip door, was it from a truck or car, or was it aftermarket? There are a lot of installs on the board but i have only seen a handfull that added a flip door.

So far i have seen people use S-10 or Chevy 1500 flip doors as the filler tubes as they screw to the flip door, or Blazer filler tubes, but in all cases the filler tube has to be modified depending the install, Also try and avoid sharp bends in the filler tubes so having to notch out the bed floor and inner sidewall of the bed and make a cover to allow for the filler tube is common.

I don't know about your frame or bed but on my install ( have not added the flip door yet) where tank sits in the frame, i figured out that the filler on the tank sits just behind one of the bed support braces right behind the rear fenderwell ( see oval hole in the frame in the pic is where the cross member sits ) so my flip door will be done a little further foward as i didn't want to worry about having to notch the next cross brace about 12" behind it to make it work.

Try searching fuel flip door, gas door ect.. or similar key words to see if you can find some ideas.