My '85 190E 2.3-16 allows separate use of fog lights and head lights or both at the same time. My '83 300 D light switch will operate the fog lights only in conjunction with the low beam headlights. How do I modifiy the 300 D switch/wiring so that turning it clockwise one position and pulling it out will operate the fog lights without the headlights? I used the forum search function and found 287 threads dealing with lighting but didn't find this question.