The free downloadable Blaupunkt St Louis MP56 owners/install manual is located here:

http://akamaipix.crutchfield.com/Man...023STLMP56.PDF

According to Crutchfield, no installation kit is required to install this in a 2004 Crossfire with factory Infinity (Non-Navigation) stereo.
http://www.crutchfield.com/p_023STLM...6.html?tp=5684
http://www.crutchfield.com/S-nuKwNU4...archivedItem=Y

That suggests that it has euro antenna connection and already has the proper harness connector.
Here's the drawing from the Blaupunkt Owners/Install manual of the harness connection

Here's the Crossfire Socket Config

Use this legend for the colors


It looks like Connector A, Pins 1, 2, and 3 are not assigned the same
- Pins 2 and 3 appear swapped
- Pin 3 in the car is not installed (but available from Becker)
Bottom line - Since Pin 1 is unused on the radio, Pin 2 and 3 are unused on the car, these three pins don't matter - if you decide to install a handsfree and want mute function, or install a sub, you'd be dealing with these pins)


But the remaining A pins and B pins are a perfect match. It looks like "plug and play" - but your mileage may vary.