[V8] Knock sensor question

[MORRALEE David]

1993 V8 4.2
while taking the engine apart I found one of the Knock sensor wires was
totally finished .
Now the passenger side knock sensor is okay and as you know this is
connected on the right side of the engine by the fuel frame rail. (
Green plug ) The drivers side ( needs replacing ) is a black plug ? I
was reading on a parts site that you need to upgrade to the green plug
type , what is the story with this ? 
 
note from the site parts site .
Note:  Green
May require 3, 000 979 133 electrical connector. Green replaces black 0
261 231 004. 
>>> what is meant by May require 3 ?
 
cheers
superdave