Replaced leaking and faulty electric fuel pump with a vacuum operated petcock/fuel valve.

Electric Fuel Pump 639861 https://www.scooterwest.com/electric-fuel-pump-assembly-vespa-lx-s-150-639861.html
Vacuum Fuel Valve 575321 https://www.scooterwest.com/fuel-tap-vespa-et-lx-gt200-575321.html
Additional parts used:
FUELLINE-3/16 https://www.scooterwest.com/3-16-fuel-line-black-rubber-per-foot-3-16-id-410-od-vespa-et4-lx50-lx150-use-hoseclip7-16.html
842523 https://www.scooterwest.com/float-bowl-oring-gasket-screw-set-for-keihin-carburetor-lx-lxv-s-150-gt200-2006-2010.html
826843 https://www.scooterwest.com/washer-for-carburetor-air-adjustment-screw-826843.html
826843-O https://www.scooterwest.com/o-ring-for-mixture-screw-826843-o.html
826780LX https://www.scooterwest.com/shoulder-screw-for-carb-top-w-m5-wave-washer-826780lx.html
IDLEJETLX38 https://www.scooterwest.com/lx-150-38-idle-jet-2006-2010-idlejetlx38-3.html

Then ultimately replaced the complete carburetor CM156005 https://www.scooterwest.com/carburetor-complete-vespa-lx-lxv-s-fly-150-same-as-cm156009-cm129214-cm129211-cm156005.html