Just depends on where you have it worked on. Ford is going to be a bit higher priced but it will also have a 12 month/12000 mile warranty on parts and labor. Just call around and take the car around and get it checked out and get prices from different tranny shops. The synchros, I don't remember exactly, aren't very much. Your biggest expenditure will be in labor costs.
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1996 Mustang GTS