Here's how to replace the turn signal switch:
(written by Midlife, link to thread below)
1. Disconnect the battery
2. Rotate horn button assembly counterclockwise to unfasten and remove.
3. Use a 15/16" socket and remove nut on end of steering column shaft.
4. Rock back and forth the steering wheel, trying to avoid hitting yourself in the face when it does come off. Sometimes a steering wheel remover is required (at Autozone).
5. Remove turn signal stalk.
6. Disconnect wire harness at base of steering column. There will be two connectors: a six pin and a two pin.
7. Using an empty ball point pen, slide the pen over each pin and gently pull the pin out of the connector. Note which pin goes to what position in the connector.
8. Wrap all pins with tape together, with a heavy string attached as a fishing line. You'll be pulling this string up with the wires, and use the string to pull the new wires down.
9. You may have to remove some hardware up top to pull the turn signal switch up, bringing the wires up the steering column.
10. On your new switch, put some black electrical tape on the back side of the switch, covering the rivet heads. These heads are electrically hot and can short out against the steering column (bad repro mojo).
11. Reverse steps 9 through 1.