Thanks. Yes, I will probably take the ROM from BeacyCove.

Now a question, is the ROM for 6100/66 any different from 6100/60AV? In that pile of old Macs we found working 6100/66 and I took it for testing purposes. I found out that 6100/66 boots and works, but the other one, a 6100/66AV model does not even chime with the ROM installed. Could the problem be in different ROM? Or perhaps the logic board is toast...