Q. Hard plate and clevise.

1/8" ply. The horn is secured using three 3/8" metal screws. Chip Hyde showed me how best to do it when I was reviewing his Double Vison. You drill three pilot holes. Then apply CA, thin or medium, to the triangular area between the screws. Then you screw the horn in place. I have tried to remove a horn fixed this way. It took an Xacto chisel-blade and swift blows from a hammer.

The Clevise can be tapped for 2.5-mm to 3-mm or 4-40. It is a hard-poly-carbon'y type of stuff... (Not very technical I know - sorry). The pin is a stepped screw that has to be removed with a small phillips driver and tyen replaced to actually fit the clevise.

I did fit a pair, back to back, with bolts to act as a pull-pull rudder horn. And one as a single rudder horn