my observation based on my 52 1/2ton panel.... where the rubber hose is the picture is where the original steel line attached to the tank.
http://i140.photobucket.com/albums/r19/LutherParris/52Panel/shacklebolt003.jpgHere is what I did. Buy a ROLL of steel line. I used 3/8 but it was originally smaller. I unrolled it the length I wanted plus a little extra. Flared one end and slide it up the chassis rail and attached it to the fuel pump. Next I put a fitting into the tank that I could slide a small SHORT piece of hose on. After sliding the SHORT piece of hose on I then attached a filter to the short rubber hose, then another Short piece of hose from filter to the main line. The line is all one piece except where the filter is and if ever a problem the filter is easy to change.
It looks really neat and should last a lifetime and the short rubber hose should also last longer than we do.
Hope this helps.
oh, I got my coil of line at Carquest. I think it was 25ft and cost $26. You'll have a little left for another project.