I used like this switch many times with great success:

http://www.odysseybatteries.com/hella.htm

An excellent location is under the battery tray facing towards the walkway
between the seats.  It's easy to get for you and the key, but very difficult
for a thief from underneath.

Cheers,

Jeff
www.vanagonparts.com

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM]On Behalf
Of Chuck Reisinger
Sent: Saturday, September 17, 2005 12:21 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Kill switch location/wiring

My last project -  kill switch....what is the best way to wire it (to
kill what)...and...good place to mount it.  I'll talked to
GoWesty....Lucas recommended running off the tac (engine will turn but
not start).....mount switch under the ashtray....local shop recommended
directly to the ALT and mount the switch where ever...what are your
thoughts and recommendations....would  love  to hear your story!

Thanks