My exploded drawing (Form 922D Section 2) shows a 'stop' (#31) PT855FH1. From the drawing, it would appear that its function is to stop the forward (toward chuck) travel of the tie rod bracket. This stop looks like it was intended to be bolted to the lathe bed using two 3/8-18X1 cap screws. If it is/was installed its only function would be to prevent saddle from traveling too close to the headstock which makes little or no sense to me. I don't have this stop with my taper attachment. Can anyone explain the purpose of the 'stop'?