Leaky saginaw input shaft

Is it possible to replace the input seal on a power saginaw steering box without tearing the box down?

 

Yes, take the box off the jeep, remove the front lock nut. Give a good rap on the input shaft with a bronze hammer. Unscrew the front retainer, making sure the shaft stays in the box. Remove the front snap ring and the seal, replace it all and readjust the retaining nut and jamb nut. You do not under any circumstance want the shaft to come out if you can help it. Most of the time the ballscrew will come with it and the balls will fall in the box, this is a major headache to fix, especially the 1st time out.