Go to a local radio shop and buy a Metra 70-5521 adaptor harness. It will have connectors for a Shaker500 and an extra plug if you have a Shaker1000. Also get the Metra 99-5807 Double Din mounting kit. Both pieces together should only run you around $35.
ONE THING TO REMEMBER THOUGH. Normally amplifiers look for +5v as a signal on. Ford in their infinite wisdom decided to use +12v as a signal on. So that means you will get a NASTY amp pop when you turn the radio on. But it is easy enough to fix. Go to Radio Shack and buy a 5v voltage regulator such as a LM7805. It will be a package style transistor. you will have three legs.One leg will be marked base, one leg marked collector ( also the metal backing might be marked collector) and one leg marked emitter. Your base leg will be input voltage, the collector will be ground ( or in some cases neutral ) and the emitter will be output voltage. So that means take the amp on lead from the head unit and put it to base, run ground to the collector, and run a wire from the emitter to the amp on at the amp. That will eliminate the amp pop.
