SCSI 1 is out of the back of the A3000 on an Apple style 25 pin D plug, and inside it's on a standard SCSI 1 low-density 50 pin ribbon-type plug on the MB.
External SCSI 1 boxes come in both high and low density Centronix connector types, it's easier to find 25 pin D to low-density Centronix leads as they're standard Apple fare!
If you have a mix of 1 and 2 devices it should work, but will end up looking messy :-(
If your A3000 has a harddisk already you may need to remove the termintors on the motherboard before an external drive can be used ... not hard to do, but hard to undo ...
And I've got a 4x reader and 8x writer for mine, the leads cost more than the drives :lol:
