At the risk of coming off as a wet blanket, let me point out that headlights, foglights and driving lights have different designs to meet different requirements.
A prime requirement for a headlight is that it not dazzle oncoming drivers. The use of driving lights - intended to be used without oncoming traffic - or fogs converted to look like driving lights, puts other motorists at risk. If you take a look at the design of your stock E36 low beam and high beam reflectors, one of the big differences that will jump out at you is that the bulb is not visible in the low beam assembly - which means that light cannot go directly from the lamp to the eyes of oncoming traffic. This is one of the jobs of the "diffuser" that was removed during the fog mod described.
*I* can see the angel-eyes of a stock installation just fine, thank-you-very-much!
