Yes it will, you'll just have to pick the faceplate of your A2000 one to give it to the A500 one (just pray for it to be the same kind of chinon floppy ;-))
Don't forget to have a look at the clock's barrel battery of the A2000 (near the keyboard connector) and change the original NiCad for a Ni-MH (Nickel-metal) 3,6v 60mA one, this NiMh does not leak with time.
