3917291....67-68...302/327/350..Camel hump, no accessory holes, 64cc chamber
3914660....327.....68....2-bolt main caps
T1117HF....Tonawanda engine plant, built Nov. 17 as either a 300 hp 4-bbl Corvette motor or a 275 hp 4-bbl motor for full-size cars.

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