[FC Zach]

This may sound dumb but it's just my 2 cents:

-Check to make sure that you have good connections at the bulb sockets (highly unlikely that all the said bulbs could have bad connections but nothing seems to surprise me anymore) It has happened to me.

-Not only check the connections but make sure the correct bulbs are in each socket. Again, highly unlikely but it's something to check. For example, I've seen single filament bulbs in dual filament sockets on peoples cars in the past.