There are 2 tiny loops of wires that poke out the back of the gauge and then you have to cut the according loop to what engine you have.
8 cyl = cut no wires,
6 cyl = cut brown wire loop,
4 cyl (2 pulse) = cut blue wire loop,
4 cyl (1 pulse and vr6) = cut brown and blue wire loops.

Cheers

Paul