You might be.
The “oversize” is kingpin diameter which is to fix a worn out of round and or oversize hole in the axle beam.
This usually is not an issue, but the oversize kingpin kit is the solution if so.
Normal procedure is standard kingpin if it still fits properly in the axle beam.
The new bushings in that kit will not fit the pin without reaming. They’re reamed to fit the pin after being installed in the spindle. This way, if done right, they’re reamed with same centerline.
Proper fit of clean parts is light press fit of kingpin in axle, might push it in with your palm, possibly a few whacks with rubber mallet.
Kingpin fit in bushings is free enough to push in with your thumb, ideally shouldn’t fall out on its own.
