Today I decided to go ahead and modify the elevator trim knob per the instructions.
This is basically a vernier control with a pushbutton in the middle to disengage the vernier
and make large adjustments. Since making large trim adjustments is very ill-advised, Vans
has you yank off the rubber button on the end and remove the push pin in the center, thus
disabling the button function. Sounds easy enough, but as it turned out, the rubber
button was attached with some tenacious adhesive. This is about
as good as I could get it with needle nosed pliers and an exacto knife.
I decided to grind out the plastic tabs in the center with a carbide burr in my die grinder.
I stuffed the center hole with a bit of paper towel to prevent plastic debris from getting
down in the mechanism.
It went great and somehow I managed to avoid scarring up the face of the knob. I also talked
to Shane, a machinist friend of mine about engraving a cover plate that'll indicate proper trim
operation.