I noticed that my reverse lights didn't come on when I shifted into reverse. I shook the stick around, put it in neutral and back into reverse, and every so often they would flash on then back off. It was obvious that the bulbs were still working.
I started searching around and found a few semi-helpful threads, but not a whole lot specific to 3rd gens. I looked in the FSM that I downloaded and it contains these pictures:
The switch is located on the passenger side of the transmission:
The switch is 27mm: