It's a '67 that started life as a 912. While dialing in my carbs after a rebuild, and putting a brick on the gas pedal to adjust high speed balance I was thinking it sure would be nice to have a hand throttle. So what years had them? I noticed while under the car the other day that there are 4 gray cables coming out of the body, 2 for the heater "flaps" and 2 just coiled up not doing anything. Could one of these be for a hand throttle?

Thanks in advance
Dave