I too use a generic 3rd light.  This one has a mounting plate that I
attached using the screw that holds the rear hatch curtain rod.

http://www.cybertrails.com/~ahwahnee/3rd%20Brake%20Light%201.JPG

http://www.cybertrails.com/~ahwahnee/3rd%20Brake%20Light%202.JPG

The single wire (it's grounded at the mounting) runs into the hatch (drilled
hole), thru the cavity along the top edge of the hatch, out thru the
defroster wire tube, and down behind the cabinets... nothing but net.  I
passed it to the engine compartment thru an available grommeted hole
(possibly one for the A/C hoses).

The light is shallow enough that the curtains close behind it.

Geo

----- Original Message -----
From: "Andrew Martin" <campahvan@EARTHLINK.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, September 28, 2007 10:52 AM
Subject: Re: 3rd brake light?

> I added one to my 85 Westy using a third brake light kit from JC Whip-me.
> To mount it to the window it has a peel and stick foam edge.  I ran the
> wires behind my curtain bars and through the grommet for the rear
> defroster
> wires.   Once inside the van body I ran the wires inside the Westy
> cabinets
> down to the engine cover.  I opted NOT to drill a hole through the rear
> deck
> so the wires go around the engine cover seal and to the existing brake
> light
> wiring...