I found an article on an American website that used a passive heat sink in the form of copper webbing loops that hang out the back of the bulb holder and can be bent to suit the space available.These were just fixed beams,not hi/low, but something of that nature would get round any fan unreliability problems.Interested to see how this project pans out,as would like to upgrade the headlamps by a plug and play method, and without the bother of adding spots.