The VSS bolts into the top of the transmission. Download your manual from the link above, it'll show you exactly where it is. I don't know what you can do besides swap in a known good one and see if the wobbling stops.
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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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