I tell what I use and it works pretty good
87-91 fords I know the vans had them . A electric fuel
pump that was mounted on the frame rail likes like a fuel filter with wires
I take one of them attach a small fuel line on the suction end of the pump and
Attach the outlet hose in a gas can put suction hose in the gas fill hole power up the pump with 12 volt’s
I can get 98 % of the gas out that way have been doing
this for years
But for god shake do not use your mouth to Siphon
Have learned the hard way
This is NOT a good thing to do
For me it was the best way