OK.
You need to get the from screen off. I usually carefully pry off the chrome plastic ring, and I then pry off the clear window. I've never broken one, but I suspect they would break easily. Some people take a dremel with a small cutting wheel and cut off the entire front about where the rubber ring is that holds it on the dashboard.
Take the two philips screws screw out of the back and pull out the assembly.
Notice that the gear has the tips of the teeth worn off, and there are metal bits everywhere.
Bend the metal frame at the lower left down. You should be able to pull that vertical shaft out. that will let you pull out the worn horizontal shaft.
Clean everything up. On the right side of the worn horizontal shaft, there is a hole in the frame that it spins in. Enlarge that hole toward the front. Basically, you want to tighten the gear engagement. From the factory, they have the gear just running on the tips of the teeth and it wears the teeth out. Once I elgarge the hole, I then fill it with JB Weld and redrill it at the new location that I want the gear to be in.
Hope that makes sense as I have no more photos.
Reassemble and lube the gears well.
When mine first failed, I actually made new gear teeth out of JB Weld. That lasted about 80,000 miles. I tried to do the same on a couple of others and they didn't last very long. And that job is tedious. Moving the gear is much easier, and I have had that last about 20,000 miles now.
