M5 in dash rocker switch installation for Lidatek LE-20
This shows the pop-out panel from the left of the fog light switch. The rectangular hole was cut with a dremel tool, and the edges filed. 

Measurements are distance from hole to edge. Narrow edges are 3 mm wide.  Top and bottom are 10 mm wide.

Switch is a 12 volt lighted mini rocker switch.

Showing switch inserted into the pop-out.
Showing wiring for the rocker switch to operate the Lidatek LE-20.

Terminals are numbered, bottom to top:

 #3 is white wire to transponder (also connects to black speaker wire)

#2 is red wires to transponder and speaker

.#1 is power (connects to fuse)

Showing switch and pop-out mounted in the dash panel.  Switch turns on/off Lidatek and illuminates to indicate transponder alert.

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