There are a range of OEM+ switches available that are identical in design to the Interior Monitoring Disable Switch, located on B-pillar trim on a Golf IV.
These include an "FS" Switch (originally used for Handsfree Device = Freisprecheinrichtung), an Interior Light Switch, a "TAXI" Switch, an "ALARM" Switch, a "FUNK" Switch and the aforementioned Interior Monitoring Disable Switch.
These switches are currently utilised in various taxis and emergency vehicles available in the German market. The picture above shows some of these switches mounted in the centre console of a Passat 3C taxi.
All these switches operate as a "momentary action" button only. If you require them to switch something on permanently, then you will require an additional "latching relay" or an appropriate circuit.
The switches have perfectly matching red illumination and will dim with the dashboard lights at night if you connect the appropriate pins from the switch to the vehicle dimmer circuit.
There is also a yellow "telltale" LED in the face of the switch which can be utilised to indicate that the accessory they control is ON. This has an independent circuit within the switch and is wired separately.
As you can see, they are a perfect size to fit on the vertical surface in the centre console behind the sliding ashtray cover:
There is enough room to neatly mount three switches in this location. Some small clearancing of the bottom of the Radio Cage is also required for each switch. You will note that the square pegs on the rear face of the centre console mount through the square holes at the bottom of the Radio Cage piece:
The extra switch in the above picture is my Daytime Running Light System ON/OFF Switch, which is normally hidden under the lower trim panel below the Climatronic. It is originally used in the Škoda Fabia II and Roomster for the same purpose. It does not illuminate at all.
These switches are also small enough to mount in other locations in the vehicle, such as near the handbrake on the centre rear console or on the lower dash trim panels around the steering column. If you have a European specification car with the Fuel Flap Release Button near the handbrake, please note that these buttons are identical in size, however the texture and style of the press button part is slightly different (smoother and flatter than Fuel Flap Release).