I believe the metal lines are 5/16" OD with an inverted flare nut. You would need a 1/8" pipe male to 5/16" inverted flare female fitting to adapt to the line from the pump to the carburetor. Check the fuel pump end of the flexible line from the frame to the pump- - - it might be able to screw into the pump directly if it's got a 1/8 NPT male thread. Another approach might be to install a 1/8 NPT male to 1/4" or 5/16" hose barb at the inlet and use a piece of flexible fuel hose and a small hose clamp as a flex line. My local Home Depot has all those fittings in stock. Measure the OD of the metal line with a pair of dial calipers - - -5/16" is 0.3125", and 1/4" is 0.250".
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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