The 74' and prior cars and the 75'-76' have different setups:

Some argue they are not fig lights, they are "driving lights"  I use them as always-on daytime running lights.

•Pre-75' - The pre-wired front trunk harness extended out of the front trunk to the openings for the fog lights and horns.  Adding fog lights is therefore pre-wired into the harness and front bumper grill area.

•Post 74' - The later 75'-76' cars have fog light harness hookups wired as plastic isolating blocks in the Frunk to connect an extra horn and fog lights.  The driver-side connections are along the fender, near the headlight bucket and also centered near the trunk latch for the passenger side.   Wires and sheathing extended from the fog lights and into the Frunk are needed to connect each light individually (not pre-wired and linked like in the in the pre-75' cars).  Once the leads are setup in the fog lights, this is just plug-and-play stuff into the plastic harness blocks with a female spade connector.  Headlight wire is White with Yellow Stripe for positive and Brown for Negative.  The switch wiring is in the correct location under the dash for additional plug-and-play setup.

•Horns?  The early cars have the horn wires in the fog light wiring that is in the front bumper grill area.  Very simple to just add another horn if you only have one.  The later cars have the wiring harness setup to add a second horn with the connection located about center (under the trunk latch) area.  For stock later cars with the 5MPH (BUBS) bumpers, the horns have downward under the bumper on the front chassis.  For that pre-75' setup, the horns have forward, inboard of the fog lights, but the grills are open to project the sound.    

 

Driving Lights on Without the Headlights on?

The 914 needs to have the headlights ON for the driving lights to be enabled.  Annoying in these modern times because having them on as daytime running lights is desirable.  Basically, the switch for the driving lights needs to have some juice to that switch, even if the headlights are not on.  There is a well-known document on this and I put that to use: https://members.rennlist.com/demick/fogrewire.html.  I used option 1b from that document with a piggy-back spade.  I also bypassed the relay by grounding one wire and the Internet has some advise on this for the patient ones here..

 

Front Trunk of the 75' is pre-wired to plug in an extra horn or fog lights.  A hole could be enlarged for the larger pre-75' grommet that takes both the horn and fog light wires or run one pair per grommet (see pre-75' harness below):

 

 

The Harness from the 74' was carved-out to show what that looks like in comparison.  The small outer grommets are the fog-light grommets.  Red paint from the 74' color change:

 

 

General measurements of about 15" of wire from the harness and they use "Flag" crimp connectors for the horn and fog light ground wires.  The larger grommet uses a larger housing to protect the wires passing through the body: