I know not to touch this, but I don't know if the previous owner did. So how can I know not to touch the Air Mixture. If someone who has a really good running carb could check to see how many turns from closed that would greatly help me out. Thank you.

 

Does not matter what someone elses is set at. All are going to vary according to the condition of the engine and other factors.

All you can do at this point is follow the procedure for adjusting per the FSM or carb manual.