Personally, I think you should not get the OE add-on changer as for similar (if maybe a little more) cost you can get much better sound quality and an overall better unit.
Advice: get the FIAT dash plate (don't bother with anything else, Autoleads or whatever, they all fit rubbish), and have a look around for a good deal. www.caraudiodirect.co.uk always have some offers on.
I've got a Kenwood MP3 headunit (KDC-M4525) in my Marea which I recommend. Autoleads do a wiring thing for it too so the steering controls work (part PC9705 I think). I haven't got that yet thought.
Good luck!
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<font color="maroon">'98 Marea Weekend ELX (1.8 16v).</font id="maroon">
- Kenwood MP3 head unit
- De-Restricted standard air box
- NGK VX Platinum spark plugs (BKR7EVX)
- Toyo Proxes T1-S (205/45) tyres on Stilo 7-twin-spoke 16" alloys
- Quad LED blue sidelights
- Type-VR Aluminum Red tax disc holder
- Richbrook Aluminium Red Uni-Hex gear knob with FIAT logo and silver/grey gaiter</font id="Verdana">