Stereo Microphone Placement

I bought and installed a new head unit. A very easy install thanks to JVC and Kenwood sharing the same plug. But I'm stumped as to where to place the microphone. As the unit supports two phones I'd like it to be in range of both seats.
 
Ideally I would like to place it up by the map lights but I have no idea how to get the microphone up there. Top of the A pillar seems to be the normal location for these but some wind noise has sprung up there (no leaks yet). Does anyone have any advice for routing microphone cables, and general placement?