The wiring clip on the Blaupunkt recievers have the same wire pinout as the ones used by the Crossfire, porsche, Mercedes, and many other German manufacturers. Plus the antenna is a fiberoptic type plug like on the crossfire, not the normal one found on mostly all north amarican cars.
If you have a limited crossfire (I'm not sure with base) with the amp you will find it will only use the front speakers on the new deck. If you are using a different type of aftermarket deck you can purchase a harness from any of the more specialized shops for around $20 a (you will have to swap the Red and Yellow wire on the harness these are switched power and constant power) and the adapter for the antenna can run the same up to about $50, you do not need the boosted one that some volkswagons use.
Hope this helps