In McDonough I would reccomend Sams, he is over on Racetrack Rd. They are really good and straight forward. All you should need is for someone to pressurize the system to see where any leaks are. After that replacement is the easy part. If you go by there, ask for Sam and tell him that Coach Towson reccomended you to come over there and see him. Now, anything performance related my reccomendation is always to go to Mainstream. This sounds like a job for any mechanic worth a shit though.