I remixed this radius gauge from @mibla: https://makerworld.com/en/models/33208#profileId-30030
The top cover is different from the original design, now every M5x30mm bolt will fit in the holder (DIN912, DIN7991, DIN7380-1,BN1435,..)
The hole has an inner diameter of Ø9,5 mm
I also made a youtube short about this project