oldandtired

Real close and thanks for the link. I am looking for a piece that by turning the knob, the cable extends or retracts.
Example - By testing, I would know that an indicator arrow at 9 o'clock would be 1,500 cold RPM. Once warm, dial back to 3 o'clock for 1,000 RPM. If the engine is running rough, go to perhaps 6 o'clock to get it to stabilize.

Make sense?

P.S. Dan, thanks for your lead. I'm checking into it and will probably make something from a push / pull cable as you indicated.