John;
I'd been thinking about your steering problem most of the day. Since an "H" is a light tractor, power steering should not be needed. All of them I've owned have steered well so just adding power steering will only be a temporary fix until the problem fails. Also, it will not be as cheap as you'd hope either.
IH used a real wimpy bearing on the front pedestal. Since it carries the entire load it would be a possibility that it is pounded out, or ran dry and failed. When you inspect it, you'll be amazed how undersized the bearing is. It will remind you of a bycycle crank unit, about the same size with very few balls.
Remove the radiator shroud (grill), remove the steering box cover. Jack up tractor and remove front wheels/tires. Take nut off and shaft will come down. Also, they are prone to snapping the shaft just above the bearing area, look for that also.
Craigdonges @ Yahoo.com