Looking for best vendors and/or correct diameter for the following items:

Hard Fuel line (3/8 or 5/16)?
Sending unit (3/8 or 5/16) Returnless? What came stock on T/As?
Any vendors have one with a brass float or purchase separately?
Vent tube diameter? (1/4)?
Brakes lines (best vendor prebent)?
Spectra for the gas tank? Anyone else to consider?

Fan?
Fan Clutch? (It was a thermostatic 070 clutch right)?
Repro dual point distributor (correct P/N 3438521?) or will look the part?
Yellow cap battery? Herbs doing those now?