Thanks av8tor for the explanation John look at 2nd picture at the start of the thread, you don't need any linkage, it's all electronically computed, a little hole gives access to the potentiometer so you can set your custom max advance for the curve, the same way you set needles on your engine. It's the same feature of the Pro-Spark Ignition (Maximum engine power is obtained because the spark advance setting is adjusted electronically by turning a potentiometer (a rheostat type device) with a screw driver while the engine is running. This usually results in more power from the engine.)
Hi Tato! I don't really put stands or sell stuff at airfields, I like to enjoy the shows with friends. Anyway sure I could take a unit for you.