Model T turn signal bushing

The Ford Model T has no turn signals, which can make it even harder to drive on modern roads. You can buy a turn indicator switch, but it is designed to fit on a round steering column with a hose clamp, and not the strange diamond shaped Model T steering column. There are adapters you can but, but for some reason they cost just as much as the switch and lever itself. Also, for some reason they do not accommodate the wining conduit that the horn switch wires run through.

This is my 3D printed version of that adapter insert.