Our 2014 Coachman 520 has the BCA Control Panel with 2 integrated dimmer controllers for separately dimming near-side and off-side roof level strips above the cabinetry. It's a nice feature but the switches to turn on/off and dim are located on their their respective front pillars which we found inconvenient to access.
I've now added two additional switches in a reasonably discrete but more convenient and accessible place. The switched themselves are simple circular momentary/retractive single-pole-single-throw (SPST) types that match the exiting switches. The new switches and original switches continue to work in the same way as the original switches. Momentary press to toggle on/off. Press and hold to dim up/down.
The new switch for dimming the near-side LED strip is connected in parallel with the existing near-side dimmer switch (existing cables run along inside top near-side lockers).
The new switch for dimming the off-side LED strip shares the 0V cable now extended to the new near-side switch (that is also shared by other non-dimmable lighting) and the other switch terminal is connected via a run up and along to behind the Master Control Panel and joins the cable that comes from the existing off-side dimmer switch. Temporarily removed the existing dimmer switches to identify cables to intercept.
All works very nicely.