I’ve been refurbishing the steering of my F40, and I am still experiencing stiff steering. Should I replace the axle bushings?
Yes, I think you should replace those bushings.
You should also check the thrust bearings on the bottom of the spindles, maybe even the spindle bearings if you didn’t replace them, but I suspect the bushings you identified are possibly the major source of the problem.
I will have to check on the part numbers to see if they are still available. Since some of these parts are common to the 50, 65, 150 and 165 they may still be available. Sometimes the bearings wear so much you have to replace the support assembly. Some of the supports are available as after-market parts, but sometimes you have to find used parts or rebuild what you have.