Indeed many 6502 systems had support for an optional Z80 (or indeed a built-in Z80, as on the Commodore 128) to run CP/M. Later there were one or two x86 boards

Indeed many 6502 systems had support for an optional Z80 (or indeed a built-in Z80, as on the Commodore 128) to run CP/M. Later there were one or two x86 boards for pre-Intel Macs. The Amiga platform's upgrade path made some later Amigas a tangled mess of different CPUs.