Early Bronco Knowledge Base Explore more early Bronco tech and history articles in the WILD HORSES Early Bronco Knowledge Base. Return to Base Early Bronco Knowledge Base Steering Shaft Mod: 3/4 Round to DD Adding a new lower steering shaft to your early Bronco sometimes requires modifying your stock steering shaft from 3/4 round to a 3/4 DD in order to fit the new steering yoke on the shaft. This is a simple process that requires a grinder and bench vice. Watch the video below, as Jim Creel shows you exactly what to do to prepare your factory steering shaft for a new collapsible lower shaft.