I know it is unethical and not the proper way to ream out king pin bushings and I'll probably catch it from others. In a pinch on some of the bushings I've installed in some axles and various other things I've repaired I've used a brake cylinder hone when I did not have the proper reamer. I hone a little and constantly check for fit. I've never had any problems with the repairs. Yeah, I know, shade tree mechanic, but I swear some of those reamers are made of gold.
Rick