how do i open the fog lights on a 1993 RX7?

You have to pull them out of the car, I think you just need a 10mm socket with extention. On the bottom of the light housing there is a cap that you need to turn to unlock it. The cap can be taken off so you can replace the bulb.

One 10mm bolt and unplug the wire and they com right out, just like IHOR said, here is a part breakdown that may help. I can't get the attachment to work if you email me at <cantgostraight@rx7club.com> I'll email it to you.