I'm using the mechanical fuel pump and I think it's 3/8ths steel brake line. I bought one 5' length from napa, it came with two compression fittings.
I also got the fuel pressure regulator, tee, two '90 degree male pipe to female compression seats' and 6 extra compression nuts at napa.
You will also need a brass male pipe to female compression seat for the fuel pump.
I got a pipe cutter, a small metal file, dual flare kit and pipe bender from Harbor Freight, and they all worked fine and were cheaper than other places.
While you are at it, you can replace the fuel line from the tank to the fuel pump if you want and also incorporate a piece of flexible hose between the pump and the metal line.
