Block casting number, driver's side rear....
http://www.speednik.com/files/2013/0...asylum-com.jpg
Head casting number, under valve cover....
http://www.enginerepairshop.com/imag...ing-number.jpg
Suffix numbers, passenger side of block deck, just above top water pump bolt....
http://chevellestuff.net/orphaned/im..._10r224695.jpg

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