I tried using Silverlining version 5.5, and when I try to "Select Drive..." from the File menu, I get...

"SCSI bus is not responding. Check that devices are connected and powered up."

Yes, an old IBM 80MB drive (with Apple ROMS) is properly connected with SCSI ID 0.

I'm stuck.

Could the SCSI bus be blown out on both Mac Pluses? Are they THAT easy to destroy?