Peter, have you tried running the CPU (060) 3x the bus speed? We know the 060 easily can be over clocked to say 60 to 75mHz.. I guess then more IC's should be reviewed.
Was thinking of daisy chaining two https://www.digchip.com/datasheets/part ... DW-pdf.php
The 926 can also output an inverted clock, which could be tested with the Falcon SDMA issues. It keeps a very tight spec on all clock outputs. Going to test this idea soon.