Hello,
I have an A1000 Zorro I to Zorro II adaptor board for the A1000 I could sell you if you wanted to go that route (using cards for the A2000/3000/4000). I also have an Zorro I board with a right-angled Zorro II connector and a Zorro I pass-thru (that you could then plug into your A590). I have used both boards on an A1000 in the past. My favourite was an A2091 with 2MB of FAST RAM on it. I didn't use an external power supply with mine. If you can picture it, I connected both Zorro adaptor boards so I had two Zorro II connectors and had another ASDG 4MB board lying flat off of that as well... Ugly, but it worked....Good times. PM me if interested.