I bought an adjustable reamer and the guide that helps ensure the reamer stays parallell between the 2 bushings and it didn't break the bank. the old spindle bushings can be punched out of the spindle using a chisel if you don't have a driver or a socket that will do the job. I usually use a punch on an air chisel to remove a groove in the bushing and thereby weaken the bushing and then a socket to push it out. clean the bore and press in a new bushing in the vice if no press is available. I don't like to hammer a new bushing in because they get mushroomed easily. once thats done then the reamer comes out and a few passes are done until the new kingpin fits well. the same reamer could be used on the axle to fit the kingpin to the new bushing installed in the 1 ton axle.
gotta be cheaper and faster at the machine shop to simply punch out a bushing to fit the axle kingpin bore.
brothers has a youtube on rebuilding the kingpins
https://www.google.com/url?sa=t&sour...4SKbbX2dyyKE72
something like this for an adjustable reamer with the pilot set
https://www.amazon.com/2-Tool-Adjust...14&sr=8-4&th=1