The issue of wear in cases where you have a harder material moving against a softer is not completely straightforward, and the kingpin issue is a good example of this.
One might expect that the soft would wear away and the hard remain untouched, but often what happens is that small bits of grit or whatever get embedded in the soft material and act to abrade the harder - this is why mild steel kingpins tend to wear more than the bronze bushes.
Granted it may not be the best idea to fit hardened clevis pins to a clutch pedal, but the basic idea of having a lathe so you can make stuff like this yourself is sound. And of course you could always do the job properly and make up some dinky little hardened bushes in which your clevis pins could rotate without damaging the pedal arm:)
