Jenn Air gas cooktop

I purchased a used Jenn air CG206B cook top and the packaging was bad. The gas valve as well as the knobs were broken. We replaced the knobs and 3 burners work fine. The front left valve was broken. We bought the replacement part and need some instructions for replacing this. We are electrically and mechanically good with things and plumbed the house for gas. We would just like some instructions before we dive into this repair...or call a repair man. Thanks you, Lynnae