For sale is a very good Winters #8521 quick change gear set with 19 and 29 teeth.  This is set 21 and in a 4.11 ring and pinion rear end this yields a final ratio of 6.29 and in a 4.86 ring and pinion rear this yields a final ratio of 7.41.  This is a 10 spline gear and very good condition.  Thanks for looking and as always I combine shipping when possible.