Help !!!!!

[The Hogdoctor]

Last week I bought a 2004 Z71 with a 5.3 motor and today I got a check engine light that came up on the dash. I went to Autozone and they put a computer on it and said that the Knock sensor on bank 2 had low voltage.
I bought another one and I figgered that if I could see what it looks like I will be able to change it out myself.
I cannot find it anywhere on the motor. Can anyone out tell me where it is located and will I be able to change it myself?
I also need to know if the check engine light will reset after i get it replaced.
If not how do you reset the computer.