I have never seen one of those, as these trucks were never available with fog lamps. I'm guessing this is from either a medium duty truck (which used the same dash through the mid 90's), or from a non-US model. Either way, it's cool!!
Ford Parts Monkey since 1985
1981 F100 Flareside - Black, 302-4V Roller/AOD
1986 F150 Flareside - Medium Fire Red 302/AOD
1989 F150 Standard Cab 4x4 - Dk Shadow Blue 302/AOD
1993 F350 4x4 Crew Cab - 7.3 IDI/ZF-5
I think it's a sickness...