I came to the conclusion that it newer existed (since there is a 8086 addon card for the M20 which can run CP/M86 and I finally thought that people mixed up that version with a native 8000 one). -- It exists. The port was actually done by Zilog of CP/M-68K, including converting the utilities written in PLH to C, then given to DR to distribute. If you look at the BIOS listings in the manual, all of the code is written by people at Zilog.