Thread
It is possible that a 'Full Install' or 'Retail' OS 8.6 CD does not contain the Mac OS ROM document in the System Folder that is the heart of the ROM-in-RAM needed for New World Macs. The Install CD for iMacs is orange, not green.
I shall have a look for you with Tome Viewer when I have a moment to do so.
de
As it happened, TomeViewer was not necessary, because Mac OS ROM was in plain view in the System Folder on the CD of the iMac-specific OS 8.6 Install CD, the OS 9.1 Full Install CD and the OS 8.6 Full Install CD.
There was an earlier firmware update for iMacs that you may not have, although that may also be unlikely if you were previously running OS X from the the same MLB.
de
There was an earlier firmware update for iMacs that you may not have, although that may also be unlikely if you were previously running OS X from the the same MLB.
de