The steering wheel remote is yellow and has ford written on it.
It also has an Amp / Tyco Electronics part number.

Does anyone know if there is an adapter for the yellow steering wheel remote that connects to an aftermarket head unit?

The white connector for the speakers and power is also an amp part.

 

Yes, they didn't make their own connectors - they bought them from many different connector manufacturers... if you look in the comprehensive wiring diagram, avialable at http://www.captainjaguarscathouse.co..._Reference.htm , there is reference to the manufacturer and model of every connector in the vehicle.