DougFreeman wrote:

I just did this repair on an S-C Series 5 machine per the video. However, I didn't completely cut out the rubber bumper, but trimmed it down by half. Worked perfectly. Don't know if the OP is still looking for the fix, but given that this is the same machine I would bet on this fix being the right one.

I also had success with that repair on a Sears Forecast 12 (rebadged SC 6-series).  However, instead of cutting or removing the bumper, I just reformed the metal bracket it was attached to (i.e. bent it outward).  That eliminated the grinding noise.