Just wanna post this small guide for those who have the EDM rear fog switch and don't know where to install it or have any confusion of what to do with those switches in the dash to the left of the steering wheel.
Step 1 - remove your USDM dimmer switch.

Step 2 - Install the EDM rear fog switch instead of your USDM dimmer switch.

Step 3 - Find a JDM/EDM dimmer switch. If you have a 92 Prelude you will also need the JDM/EDM switch plate (see 2nd photo). If you have a 93 Prelude then the JDM/EDM dimmer switch will fit into one of those blanks near the e-brake.

92 Preludes. You need this JDM/EDMswitch plate. It fits into that storage compartment in your center console.

Step 4 - Run those USDM dimmer wires to the center console where your JDM/EDM dimmer switch is. Remember that the JDM/EDM dimmer switch does not have a bulb, it does not light up. Therefore it will be 1 less wire to deal with.
That's it. Hope this clears up all the confusion about what to do when you wanna use the EDM rear fog switch to hook up your rear fog light. You don't need to tuck anything behind the dashboard. You can still keep your dimmer or cruise switches.
You can also use this guide as an idea to hook up the EDM Rear Fog Switch to your front fogs as well.