Hints on solving front end 'wobble'..

[Tom in TN]

'34 coupe, with fresh front end parts and a steering box redone by Josh Mills...

Crusing along the blvd and go over a railroad track...front wheels start flopping side to side so bad the car almost stops. - after shaking my kidneys loose...doesn't happen every time, but if I don't have the wheel turned so as to load it to one side- look out.

Toe-in as about 1/16th. Caster/camber is factory.

Any likely suspects from your experience?