[GMCPaul]

I'm not sure what you may think you need adapters for other than the vent lines which you use hoses to connect to. The tank has 3 vents and 1 fuel filler. You attach a 1 3/8" hose to the fuel filler, a 1/2" hose to the fuel neck filler vent, and the other 2 connect hoses to them and get 1 way check valves and attach them to the end of these 2 vent lines, I then use the metal fold over type straps to attach the check valves to a bed cross sill. Connect fuel line to fuel sender, and fuel sender wire to tank sender.
I've attached a pic I borrowed from another thread where someone else did it basically the same way but they plugged 1 of the 2 vents I place a check valve on myself. I like 2 check valves as using just one on a really hot day the fuel tank may burp when filling getting gas on you or down the side of your truck due to rapid pressure build up.
Paul @ GMCPauls