1 The process of rust-proofing your headers requires only a few hours. It is best to use new headers that don’t have contaminants embedded into the metal. These are a new pair of headers that were ordered bare. If your headers arrive painted, they will need to be sandblasted or sanded to get to bare metal. Also, make sure to mock up the complete exhaust system ahead of time to make sure everything fits up properly and weld up any mounting tabs beforehand. Notice that we’re also going to be treating the muffler.