To my knowledge A2000 roms won't work in an A3000.
My A3k was a SuperKickstart machine, and as long
as you don't want to run an accellerator you can
use any KickStart file you want from KS-1.3 to
KS-3.1.I still have the KickStart files but I
installed OS3.1 roms (there are 2 roms) so I could
use my WarpEngine accellerator.