For future designs I did some CAD construction that fits to a longboard kingpin. The magnet will be stopped from rotating and hold your optic in the position you want it. You will find lots of round neodym magnets in the internet or in hard disc drives but try to find a thick one that will keep enough force to the kingpin. The surface the lamp sticks to the iron should be as huge as possible. The nut on the backside will keep a lamp at his place and reduce the LED temperature. All joins are done with Arctic Alumina Thermal Adhesiv. The optic is still under construction. By changing the shape of the space blanket the reflection of the light can be controlled in a way, so that other road users will not get blinde. I will show this in detail in some future steps.
Here the CAD Data: