I think "Audio control" makes the processor. It comes with a seperate volume knob that you mount where ever you want.
Heres a more detailed video from the same guys that sell that mount. It shows the install and connections etc. pretty cool if you ask me. Since my dash is already cut, I have no problem trying this. Im going to place the mount overtop of all the sheetmetal so I dont even have to cut anything, but I will lose my ashtray. If i like how it works, I will cut it into the dash and make it flush later.