dmpdave has it right. Raise or low a vintage bridge with the screws. Raise or lower a Newark Street bridge with the provided Allen wrench instead of a screw driver.
I had a set of saddles made many years ago and they are are taller than the standard saddle. Turns out the bridge on that bass is is as flat as it can be and the action is my favorite.
Keep in mind that there are limits to action and intonation and as a consequence there are many vintage basses with replaced bridges. Hasn't been a problem for me but YMMV,