Using Auxiliary Fuel Tanks

Hi! Just a quick question any body here ever put in duel fuel tanks with a switch to go between them? Thinking of putting two auxiliaries under driver and passenger seat reason for this is hoping to tour Europe in it next year carrying extra fuel will be a big help. Currently driving a 95 110 300tdi. : )

You could plumb them all up as one lone but put a solenoid operated stop cock to act as an isolator, just don’t run out though.