Thumb rest for Rickenbacker 4003 (Recent models 2014-2017) that fits without the need for any modification to the bass. There is a standard version or a bevelled version. You can choose whichever you prefer. The bevelled version does give more room if you still want to rest your thumb on the neck pickup.

My Rickenbacker is a 2017 model and I believe that any model prior to 2014 may have a slightly different spacing between the mounting holes, so this will only fit newer models. If you send me the exact measurement between the two mounting screws on the scratch plate. I could modify the design slightly to see if it fits.

Prusa i3 MK2

0.100

You don't have to print at a high .50 or .100 resolution but as it is a small and quick print, you might as well go as smooth as possible especially as a Rickenbacker deserves the best :-)