"The same device I told you about that plugs into the A600 clockport, also plugs into the A1200 one"
The A600 does not have a "ClockPort".
Both A6 and A12 have expansion ports.
Niether 2 Layer European nor the 4 Layer American A600 PCB's have Clockports.
Perhaps you meant another HW product that fit over a PLCC chip?
Please elaborate...
...and YOU with the schematics in the INBOX: Share-em!!