Couple questions for everyone?

[cmyc5575]

Ok I have an 82 gmc sierra that is going threw some rust resto and need to order some repaire panels that are tough. Where is the best place to buy them at? I was told to stay away from LMC becuase the quality isnt there for the price your paying and the material is thin.

2. My windshield wipers are working just fine but on the switch themself you can push the button rod in and I hear a loud pop sound and feel some kind of vibration in the gas pedal and brake pedal, any idea what is causing this? Is pushing the button on the switch some kind of mode for the wipers. Also I can turn the knob but does not do anything different when they are running.