Electric powersteering?

Also, there's another option that might or might not be workable. It's an inline hydraulic amplifier. I guess some guys use 'em on off road stuff. It's simply a round cylindrical object, shaft in and shaft out, and hydraulic fittings from the pump. It also goes right in the column. Tractors, notably IH (Farmall) use 'em, also called a "Char lynn" or torque generator or torque amplifier

Here's one all taken off. The actual booster device is the object at far right



What this might do:

You would of course still need some sort of pump. But if you have header, etc problems, and don't want to spring for a Borgeson, you might get lucky and score a fast ration manual box.

Then you can stick this up under the dash. Yeh. It'd be a lot of work.