Hi -
Please be aware that the king pins get sticky and rusted - Best bet is to strip, clean and reassemble with liberal application of grease.
The steering chain also gets "tight spots" - best to remove and soak in solvent then lubricate with a dedicated chain lube.
The steering shaft below the wheel, just above the steering box could also use a spray of lube
Good luck - that steering box was not a great idea (in my humble opinion!)
