I helped a friend install a switch which cuts power to fuse panel. It was a good heavy duty  marine switch with a key, and was pretty well hidden. The interior lights, radio, and camping stuff were on a separate circuit.
He can easily turn off power to the panel when he feels like it

I worried about switch failure stranding him, but if you know where to go, the switch can be by passed. It has worked for him for about 8 months now.

alistair
 
On 2011-10-21, at 12:45 PM, Richard Koerner wrote:

> Wondering how many of you volks have installed a hidden switch in cab to cut voltage to fuel pump as getaway-deterrent?  I've been thinking about doing it, would be easy enough and plenty frustrating for car thieves, but always seem to talk myself out of it.
> 
> Rich 
> San Diego
> 
> --- On Fri, 10/21/11, ed donnen <spliced.surprise@GMAIL.COM> wrote:
> 
> From: ed donnen <spliced.surprise@GMAIL.COM>
> Subject: Hoods in the van
> To: vanagon@GERRY.VANAGON.COM
> Date: Friday, October 21, 2011, 12:29 PM
> 
>> remind all of you out there in Vanagon land to lock your doors.
> I never locked my 81 bus except once, in DC, at my wife's request.  Nothing
> of value was taken because nothing was in there, but I made her pay for the
> window.
> Window cost more than anything inside and a van makes a lousy getaway car.
> ed-saving my windows one day at a time