A word about using a tap as a chaser vs. a slotted bolt - The tap is designed to create the female threads you are cleaning, and will thus do the best job of refinishing and cleaning them of rust. The modified bolt is actually slightly smaller in diameter, and will leave more residue to seed future oxidation. This is why a particular size tap will not thread into its complementary die.

Steve

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'91 MB 190E 2.3
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