I just noticed you're in Germany. I'd suggest taking your spindles with the new bushings installed, and your new king pins to an automotive machine shop and giving them a clearance specification of .0025 MM. That's the equivalent of a 1/1000 inch slip fit. That would be about the clearance obtained with an adjustable reamer. If power honing equipment is available, it would be possible to get a .001MM clearance, or closer, but it's necessary to leave a little room for lubrication. Chassis grease has a hard time squeezing into gaps of less than .002MM or so.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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