@stachu100
That isn't entirely correct though as I have a perfectly working 603e+ with 060@66MHz, working also @75MHz if I remove one of 2 128mb simms. 060 isn't even rev.6, it's rev. 5. SCSI works fine of course reaching almost the bus limit of 10MB/sec (9,7MB raw read according to drivespeed utility).
So, maybe there are other factors limiting the clock speed in your case.
