A friend got me a Parrot 3200 colour handsfree kit for 20€ (used, not stolen).
Took the radio off and wired the kit. It's really simple, the harness has to be connected in series with radio (both power and speakers connections), so it turns on and off with ignition and automatically mutes the radio, even if the radio is one of those that require a special connector to enable mute functions (as does my blaupunkt london mp35).
As I didn't have a fixing bracket for the control panel and didn't want to glue anything, I fabricated a bracket out of scrap copper sheet I had around, el cheapo's way. The bracket went nicely into the seam under the right side of the indicators pannel, nothing rattles or shakes, no screws, no glue.
Unfortunately I can't see the screen very well but still I can pick the calls without taking risks (fine is 500€, an accident, even worse).
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