What John was suggesting was shimming the vertical split between the outer and inner parts of the apron (see arrow in pic). this would have the effect of moving the gear out away from the bed.

However, judging by the position of the marks on the bed the binding isnt the gear itself but the end of the shaft on which it is located. I'd have thought taking a light grind off the end of the shaft/gear face (a few thou) would resolve that without compromising the peening/fitting...

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