It's not necessarily the mileage of the motor, it's the condition of the motor. Do a compression and leakdown test, and if they turn out ok you're good to go. You don't need a window switch, but it is a very good idea with your auto tranny.
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2015 Ford Mustang GT Fastback - Ingot Silver - 6M - Performance Package - Gibson Catback, JLT CAI, FR 47lb injectors, BAMA E85 tune, Eibach Sportline, BMR wheel hop kit, UPR oil separator, Steeda shifter bushing/bracket
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