A fine toothed machinists file w/ light strokes, held a bit diagonally will dress out marred surface imperfections, rotate file around circumference w/ each lap over dinked area so it does not 'flat' any part of the axle or shaft. Don't try to get it all at once, keep trying fitment to housing before removing too much metal.. (fine toothed bastard file & a drop of oil and 10 minutes)
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