When I built my RV-10, I did not like the way the Andair valve selector lever could easily rotate out of the indent without having to lift the safety knob, so I filled the pin channel with JB Weld and drilled it out for the pin at the Left/Right/Off positions. That gave me positive position locks in all three positions and the only way to change it was to lift up on the safety knob first. No way it would accidentally move by being bumped . Doing the same on my RV-9A.