Minor electrical problem

I have an annoying(only because I'm a***l rententive) on my 1981 911SC and my wifes' 1984 Alfa Spider. The small problem that I have is that the left front parking lights don't work. I have gone through all of the wiring and checked the bulbs but to no avail. The turn signals work ok but no parking lights. THIS REALLY BUGS ME!

Also, the rear lights work ok to. Does anybody know if the parking lights are diode isolated from each other or have seperate circuits after the fuse? Any help would be so greatly appriciated.

Thanks in advance,
Dave
1981 911SC
1984 Alfa Spider