The screws in your second pic.
Ok I guess it's not entirely clear in that thread, but
post #7 in that thread does mention:
The 4 spoke air bag comes off just like a 3 spoke. Disconnect the negative cable to the battery and you need a T30 torx driver for the 2 torx screws behind the wheel.
I now remember I did some additional searching on renntech looking for steering wheel removal before diving in, if I find it I'll post it. It's pretty straight forward, just a little nerve wracking working with the air bag.