If you use chinon mechanisms, they will fit.
Also the eject button can be swapped out of the A3000 drive.
A2000 and A4000 chinons might also need a little bit of the outside cover snipped from the top edge in order for it to fit, in addition to removing the face plate. (at least the A500 does, the last time I owned an A3000 was 7 years ago..)