Summary

That title sure is a mouthful ;)
I basically liked the thing:79834 bracket for the RPi, but thought it was a bit too exposed, so I added the OctoPrint RPi case to it.
For the bracket. I made the clamping parts a bit longer, as the original didn't quite get all the way around my prusa frame. The ABS version is a snug fit, while the PLA version is 1mm wider, so it fits around the frame and the pin-thingies don't snap off.
For the case itself, I removed the mounting holes on the side and made two holes that fit the bracket in the bottom part, while leaving the top part original.
Depending on what you prefer, you can either use shorter screws with fitting nuts and just mount the case to the bracket, or you could use longer screws and go right through the RPi mounting holes, as well. (M3 screws and nuts)