| I hope this post will clarify some issues relating to fog light mods in the Z32. Most of the confusion centers on the fact that there have been two (2) different types of Fog Light Mods presented over the years: The first type deals with the fog light relay power source; the second deals with completing the relay grounding circuit. All of the Fog Light Mods should really be termed the Fog Light SWITCH and RELAY Mod because the changes are being made in the way the fog light relay gets its coil-side power and how the dashboard switch completes its grounding the relay’s ground circuit. None of the fog light mods change anything related to how 12 volts / 35 watts of power is routed to the fog light bulbs. Those circuits are not modified. It is necessary to understand how relays work before you can understand the remainder of this post. If you need a primer on relays read the following or do some more research on your own.
A relay is a device that allows you to control a high-current electrical load with a low-current electrical 'signal'. They are usually electro-magnetic, but are also available in solid-state forms. They can be used with a switch (to allow control of a high-current load with a small switch) or they can be hooked up to a switched power source in the car like the ignition or accessory power circuits (to allow power to be switched on/off automatically with the ignition key). 
Fog Light Relay - Grounding Mod
JaimeZX wrote the first fog light mod. He approached the issue by changing the way the fog light relay complete its ground side circuit. You can find his post in FAQ here: Jaime ZX Fog Light Mod as Found in FAQ In a stock Z, grounding the fog light relay follows a circuitous route back through the headlight and dimmer relays. This grounding mod changes the relay coil grounding circuit, but it does not alter the OEM source of relay coil power. JaimeZX decided to eliminate the ground loop through the dimmer switch and headlights and simply ground the fog light relay wire (G/Y) to the nearest ground in dash switch module. In the OEM circuit the fog relay ground itself through the dimmer relay, which is why the fog lights deactivate when the high beams turn on. It appears by his post, Jaime wanted to run both together. In this mod, you still need to have the headlights switched on because the OEM Pass Side Headlight Relay is the still source of power for the Fog Light Relay Coil and nothing has been done to change that. Only the grounding circuit has been changed. The fog light relay still needs power from the Pass Side headlight relay. Conversely, the fogs will not activate when the headlight switch is in the OFF position as one might want in order to use fogs as substitute Daytime Running Lights. Fog Light Relay - Power Source Mod The above mod deals with the grounding side of the fog light relay. This second mod deals with the power side of the fog light relay. This power side mod is the one most often performed; and it involves changing the headlight relay power source to another source. As noted above, in stock form the Fog Light Relay Coil derives power from the Passenger Side Headlight Relay. The mod involves splicing wires under the relay / fuse box located on the Driver’s Side Fender well. Red Hawk (CO) did a Power Side Fog Light Mod. He replaced the OEM Pass Side Headlight Relay power by using the AC Fan relay source to power up the Fog Light Relay Coil. The page may be found here: Red Hawk's Fog Light Mod using AC Fan Power When this mod is performed, the fogs can operate whenever the headlight switch is turned on, be it parking or low beams. However, unless the above noted grounding mod is performed, the fog lights will still not be able to operate independently because they still need to use the OEM grounding circuit, and that only functions when the headlights and dimmer relays are hot. There is more flexibility in switching with this mod, and now the fog lights work with both the parking and headlights. Plus you have the flexibility of choosing which power source to use. Red Hawk’s mod uses the AC Fan which is only hot when Ignition is turned on. So fogs will shut off when the engine is turned off. Some other mods find might use a constant 12 volt power, so the fog lights shutting off now are dependent upon to deactivation of the relay coil grounding circuit, which is linked to headlight operation. Remember this mod only deals with the power side of the fog light relay coil. To finish its circuit, the fog light relay coil needs to be grounded in order to complete the circuit and close the relay.
The Combination Mod - Independent Switching and Auto On/Off Power If you want fogs to operate completely independent of any other driving lights, then you need to perform BOTH of the above mods. There needs to be a new source of fog relay coil power from someplace other than a headlight source; AND the a different fog relay grounding circuit needs to be established. I did both mods and now have complete independent control over fog light operation whenever the key is switched to engine run position. The relay power is sourced to ignition switched AC Fan relay and the ground circuit is completed at the dash fog light switch per the JaimeZX mod.
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Fog Light Mods - Fog Relay Power and Fog Relay Ground - 
