['65 chevy lover]

Finally got it done. There was a small plastic cover on the inlet of the tank. I put red lipstick on it and raised it up so it would touch the under side of the bed when lowered. Then, raised the bed up to put a pilot hole in it. Then lowered it down to drill the big hole with a hole saw. Then put hose, filler nozzle and clamps on. Then, I was able to look between a 1/2" crack between the bed floor and frame while reaching thru from the left side and tighten the clamps. I was barely able to get my arm far enough in to reach everything but, got it done.Damn to have that done!
Edit: If I had it to do over, I would have used a regular type gas cap with a hinged fuel door. Would be WAY easier!! In fact, when I get around to replacing the bed wood, I'll probably switch over.