There are two types of Fender 6-Point tremolos. The difference between the two is the string spacing measured across the saddles at the bridge. There is WIDE 2-7/32" string spacing, and NARROW 2-1/16" string spacing. Wide spacing represents the original Fender tremolo. Narrow spacing tremolos are often found on modern import Fender guitars. 

The photos below show how to measure your tremolo to determine which bridge you have