Hi fellow vanagon freaks-
To get away from the antifreeze debate fo a moment:
On both the driver's and passenger's side I can recommend creating two
discreet storage areas for valuables by  carefully removing the carpet on
the front vertical surface, cutting out the metal rectangle blocking the
empty space right under the seats, then creating drawers that slide in from
the front. The carpet can be velcroed to go back into position so that these
drawers are hard to spot for any thieves who are in a rush.  And they can be
easily reached by the driver and front passenger.

Re the bigger compartment accesible from behind the seat, I've got my 2nd
battery in there with fuses etc. But on my earlier vanagon I kept my tow
rope, jumper cables and emergency tire filler there - perfect fit.

Peter Lackner
Santa Barbara