i am no good at explaining , but this should help you
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well this was on a 2009 challenfger SRT 6.1, i looked on another site that was talking about 5155177 these are good for 2006-2010 6.1, but but some are also swearing they work on the r/t models as well
but but some are also swearing they work on the r/t models as well (This part you would have to research yourself, but i heard this before, and again i am not confirming this)
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