A few things to keep in mind here:
1. Apple HD SC Setup will only see Apple-branded hard drives. Even if you swap the drive with a non-Apple ProDrive, for example (very common brand in SCSI-equipped Macs) it won't recognize it. Look for an Apple logo either on the drive itself or on a sticker on the drive.
2. If you have another Mac, you may want to test the drive in there. Alternately, look for an external SCSI enclosure and try to fit the drive to that. This will rule out the actual drives being bad.
3. You had mentioned some utilities for checking SCSI connectivity. Either SCSI Tools or SCSI Probe will work here. Both should be available on the shareware/freeware sites.
4. Regarding the Quantum ProDrive LPS--were there any known issues with it when it was last used? Also, be aware that these drives are starting to die out after nearly 20 years. I've had more ProDrives die in the last two years than I have in the nearly 22 years I've worked with Apple hardware. (Most, however, have been of the ELS variety).
1. Apple HD SC Setup will only see Apple-branded hard drives. Even if you swap the drive with a non-Apple ProDrive, for example (very common brand in SCSI-equipped Macs) it won't recognize it. Look for an Apple logo either on the drive itself or on a sticker on the drive.
2. If you have another Mac, you may want to test the drive in there. Alternately, look for an external SCSI enclosure and try to fit the drive to that. This will rule out the actual drives being bad.
3. You had mentioned some utilities for checking SCSI connectivity. Either SCSI Tools or SCSI Probe will work here. Both should be available on the shareware/freeware sites.
4. Regarding the Quantum ProDrive LPS--were there any known issues with it when it was last used? Also, be aware that these drives are starting to die out after nearly 20 years. I've had more ProDrives die in the last two years than I have in the nearly 22 years I've worked with Apple hardware. (Most, however, have been of the ELS variety).