My 54 had was basically the same set-up. My solid line out of the tank was 5/16"...I ran a copper line inside the frame....used a 4" piece of fuel grade rubber line with clamps at each end to tie it together and as a vibration absorber. I just use a set of needle-nosed vise grips to pinch off the hose when I want to shut of the flow. Hope this helps.
