Well, the A4000T mainboard should be AT form-factor, so any tower that will take AT boards are sufficient. Expanding the Zorro slots seems impossible though...maybe with a Prometheus you can gain some PCI slots, but I think you will block a lot of Zorro slots by using it. The G-Rex PCI adapter for the A4000T adds 3 PCI slots without interfering with the other slots, as far as I know. The Mediator would give you PCI-slots, but will cover the ISA slots. It's a choice of evils IMHO.
