[Roadsters] Reverse Light Wiring Help

[wattaj]

I need help with the wiring route for the reverse light.  I see the wire
coming off the fusebox through the firewall.  I have not been able to trace it
beyond that.  I am assuming that it drops down to the transmission tunnel and
then back up before heading to the rear end with the other tail light wiring. 
When I bought the car it was not connected at the transmission, and I don't
see any wire in the transmission tunnel to connect.  Thanks in advance for any
advice.
 
Cheers,
Alan
67.5 1600 Roadster
Tualatin, OR