not really like scsi - that's more like usb with a central controller. more like VME - a bus that looked alot like a 68k bus, but supported multiple masters with a protocol to negotiate temporary ownership to assert a transaction.

there was a single address space. so every board had a set of dip switches to give it its address. which was always a big source of pain

I can't imagine apple shipping a computer product like that, so maybe you get the high bits based on what slot you're in and a config eprom to do discovery?