This was in my MX5 when I first purchased it - was working fine but has been removed to make way for a new head unit.
The display stopped working just before removal but I'm not sure if it is due to a bad connection (separable security flip display) or something worse ... in any case, it still plays CD's fine when you insert them.
Model # is DF600W - has 4 x 45W + usual MOSFET chip.
I also have the credit card remote control and security case for detachable front. Have cut harness at back in replacing it but have retained the connector - no instructions though but I guess you can download it off the web somewhere.
Asking $30 and am in Brisbane - can post interstate too.