Well, still... Booting an iMac from floppy at all is a huge accomplishment!

It seems like downgrading the firmware isn't the answer; somehow getting Mac OS ROM versions > 1.1.5 to support that driver is the key.

Anyway, perhaps I can try this on my Rev. A/B; I did a lousy job soldering on the connector first time 'round, but this inspires me to try again!

c