I just broke the plastic piece that the turn signal arm mounts to, does anyone have the part number for this? It is extremely difficult to use the blinker at this point, and using hand signals is really uncool.

 

I think you're referring to the turn signal switch. If so, GM part # is 1995963. But you should be able to find it at Autozone as well.

 

Just took the car to the dealer and had them do a diagnostic inspection. Apparently the part that broke was the high beam switch (on gmpartshouse it's referred to as a wiper switch); part number 26098535 and he said the lever itself was broken but I haven't had any problems so I don't know what the heck he's talking about. That was P/N 25140743 fyi. The switch is $118.74 at gmpartshouse so I'm gonna dive into this one solo (dealer wanted $930 to fix it).

 

When you pull back on the turn signal lever, it pushes a rod forward that pushes on the headlight switch at the base of the column (exact same place as the starter switch).

http://shbox.com/1/steering_column_exploded.jpg

The rod is #77, and the switch is #83. The switch is cheap (about $12 at Autozone) and easy to replace, but the rod can be a PITA. That price from the dealer is highway robbery, which is why I never let them touch my car.

 

On that diagram, the piece they said I broke was #23.