Rent a dehumidifyer from a carpet flood damage place to start.
Leave it in the car 24/7.
Copper mate told me of a Divvy van stuck in flooded Melbz freak downpoor.
They couildnt tell the upper eschelon so got his Mechanic brother in to see if motor OK and it burped up all its water on hand crank , plugs out so good to go. Car was hidden up back of the station carpark and run 24/7 with heater on and A/C , till all dry but squawker module undewr seat not OK and really did sqwawk........ and it had to go to the garage at Cop central repairs , lots of water came out of module but nobody got in the shit!