Idea:

Run a 68000 emulator on a PC, and connect the PC to an existing 68000 system, replacing the CPU with a ribbon cable going to the PC.

I realize the emulation would not be cycle exact, but that is not the goal.

Question: how much would it take in terms of glue logic between the systems, minimum?

I have some crazy ideas:
IDE port on PC is 5 volts. IDE is basically a 16 bit parallel port.
The 68000 has 16 bits data bus. Maybe some latch to keep the 20 bit memory address? Reset flanks could be stored in and read out by emulator?