The factory radio is modular. There should be a blank looking plastic piece toward the bottom center of the face that you can pop out and plug in a tape or Mini-Disc player and works just like it's part of the radio. If you were to pull the radio out of the dash you would see that the whole bottom of it is pretty much hollow to accomodate the attachments.
too bad the price for it is s***, for the price of a MD player in your factory deck you can buy like a double din CD+MD player with tripple preouts blah blah blah
New 2025 CX-5 with highway vibration problem; tires?