2001 Pontiac Montana crank shaft senser

i have a 2001 pontiac montana van and i know what the problem is with it i just dont know where it goes the van has 2 crank shaft sensers in it and one is bad so the van isnt running right so i have bought both sensers and i know that one is on the side and one is behind the motor but i dont know which is which or where on the side it is talking about or where behind it is talking about can u send me a pic of a motor and show me where they go thanks so much my email is elizabeth.beard1981@gmail.com thanks again elizabeth