I have not done it on the X5 but have upgraded H3's before. As for the fogs, I don't think you'll have much to gain but if you really want to do it I would get a wire harness to handle the extra wattage. www.4x4connection and www.bb4wa.com sells such a harness from ARB/IPF. It's almost plug and play. You should also take into consideration the extra heat that will be generated in the housing.