Kyle,

Replacement floating bushings (I've only seen metal bushings) do not have to be reamed - standard and over-sized.
3/4 ton trucks had different style bushings, depending on the year.

1942-1947 (and, most likely for several earlier years).

1948-1951 (through at least 1955-1st series trucks).

The The king pin Tech Tip is for 42-46 trucks..

Tim