You won't get an accurate measurement on the bushing until after it is installed in the spindle.
Uninstalled chances are it is not completely round and you can't account for how much it shrinks/compresses when installed. It could be loose now, and to tight when installed, which would then require reaming/honing.
You can however get a guess at it, if it slips over the king pin now then likely it does not need to be reamed after instillation, but this is just a guess, the real answer comes after you install the bushings and test fit the pin.
Grigg
