The suffix code is on the little pad in front of the passenger side cylinder head. Probably have to swing the alternator back to see it. The number is stamped not cast. Usually have to clean it off to read as sometimes the stamp is not very deep. One set of the numbers is a partial vin of the vehicle it came from. The other has the suffix, it is the last 3 letters. After you write them down, check out www.nastyz28.com.
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