It would probably be possible to adapt a later model spindle to the existing kingpin mounts. We used to install a 3/4 ton Ford rear axle load tube to the right front hub and run a "wide 5" front wheel and brake on the dirt track cars. A good machinist and welder could probably do something similar with a 3600 steering knuckle assembly. I'd probably cut off the existing spindle, bore a hole in the steering knuckle, and fabricate an appropriate-sized spindle from bar stock and press and weld it into place. Another method would be to turn the existing spindle down to a straight contour and press a fabricated spindle over it, then make a weld back at the steering knuckle. Difficult, but not impossible!
Jerry

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