The best/safest and most efficient way of getting those done is to bring 'em to a machine shop....it should only cost a few bucks, and you will end up with a professional job.

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00' C230K
88' 190E 2.3
79' 280CE (Sold)
84' 300SD
73' 450SE
93' 300E
68' VW Bug (what the hell was I thinking!)
99' HD FLSTF