Well now swapped to rose joint steering, bars are twice the size of the o.e. rods. Drilling the hubs was simple as they are soft metal. Pitman arm was slightly harder and required resharpening due to the edge tips going dull. Managed to get all three holes drilled and teamed before the drill gave up. Just need to redo the bracket for the steering damper.
20mm rose joints and cap head bolts certainly tighten up the steering control and has minimised some of the wander.