By Charlie White, Bruce Baker, Martin Boecker, Frank Earle, Alan Klingen, Joris Koning, Joost van der Velden
Charlie White: My 65-C Coupe has the fog light switch to the right of the clock. The position near the ignnition switch is shown in a 1962 Service Bulletin that applies to 356-B's.
The fog light and switch for 356-B T-5's is first covered in Factory Service Bulletin SB 41/59, December 1959, in which it says: "To mount the pull switch (spare part No. 644.613.501.01) a hole of 5/16 diameter must be drilled through the dash on the same level left of the ignition switch at a center distance of approximately 1 9/16 inches." Note the part number.
Subsequently, in Factory Service Bulletin SB F 1/62, it says: ""When installing the pull switch, spare part No. 644.613.501.01, for fog lamps which is located above the ignition/starter switch....." Again, note the part number which is the same as in the earlier bulletin. Below is SB F 1/62. Note in the drawing that the switch has the yellow center on the pull knob.
The two bulletins indicate different positions for the fog light switch: the early bulletin for the T-5 B's says to the left of the ignition switch, and the later bulletin for the T-6 B's says above the ignition switch.
I believe the reason for the change is due to the position of the windshield wiper switch. In the T-5 B's the windshield wiper switch was above the ignition switch, so the fog light switch was placed to the left of the ignition switch. On T-6 B's the fog light switch switch was moved above the ignition switch because the windshield wiper switch was moved to the right of the clock which was centered in the dash.
On the 356-C's the fog light switch was mounted just to the right of the clock which was centered in the dash. This was due to the fact that windshield wiper switch and the cigarette lighter were moved below the radio mounting area on either side of the ashtray. You can see all this clearly in the images in the various owner's manuals. There are probably lots of exceptions to this based on who installed what when.
Below is a scan of the Factory Service Bulletin SB F 1/62.
Alan Klingen: a copy of the factory installation page shows the switch about 1 1/2 inches to the left of the ignition switch.
Frank Earle: I had to figure out where to place the fog light switch on my '58 cab. After researching this question, I learned, thanks to a photo from a registry member, that the switch was located to the left of the ignition switch at the same level, equal distance from the dash radius and the ignition.
Joris Koning: On early Carreras (T2) the fog light switch was just above and slightly to the left of the cigarette lighter because the fuel pump switch was above and to the left of the ignition switch. In every other instance the factory on T2 closed and open cars with the exception of Speedsters would mount the fog light switch to the left of the ignition switch.
Martin Boecker: For a T5 the switch is to the right of the clock, symetrical to the cigar lighter. I have not seen original T5 without clock but with fog lights.
Joost van der Velden: My 1962 BT6 S90 was delivered with foglights according to the official Kardex. The switch is located above the ignition switch.
Phil Harris: On my old '64 356C Carrera 2, the fog light switch was to the right of the clock and was factory installed (optioned) from new in this position.
Bruce Baker: The fog light switch was wherever Porsche's guys thought it should be. I worked on a '63 T-6B with foglights mentioned on the COA and on the car, but no switch in the "typical" location(s). Looking at the back of the original dash (original paint front and original overspray of ruby and primer on the back, there was never an added hole drilled or filled. There was, however, a chrome toggle switch under the dash, a screw connection "period" switch, with no illumination light. They likely ran out of the "usual" push-pull lighted switch that day and it was the best they could do. It was a "Euro" car, so maybe it was to be dealt with later.
Factory photo of a 356C Cabriolet shows the fog light switch between the tachometer and the speedometer.