@SaltWaterDrinker
The switch box is mainly for the "air components" in the TB. I´ll go with a arb airlocker in the rear axle when the ext axle is installed. That´s the first switch.

The second switch is for switching the on board air on, the gauge shows the pressure in the tank.

Both compressors fill the tank up to 8 bar, the pressure switch shut the compressors off when the 8 bar are reached.

The third switch can increase or decrease the pressure in the airlift1000 bags in the rear coils.
The last switch is for functions in the future..
@James
Have test driven that setup today and there are minimal vibrations, much better than it was. Only thing which takes getting used is when looking in the passenger side mirror there is "more information" for the eyes. Don´t know how to tell it but have to be more concentrated when looking in the passenger mirror.