The A1000's expansion slot is on the right side, so the A590 would face back, and slightly higher, so you'd have to make a little stand. Otherwise it should work, but you can't be sure until you've tried.
Using a 1.3 Kickstart disk would enable you to boot from HDD (Kickstart from FDD, of course). Getting a ROM expansion to be able to use 2.x/3.x A500/2000 ROMs would be the next step then - might be hard to find.
