I PURCHASED A 1967 EL CAMINO RECENTLY. THE SELLER HAD THIS SHORT BLOCK AND WAS GOING TO HAVE IT REBUILT, BUT NEVER DID. ANYWAY, I AM TRYING TO FIGURE OUT WHAT I HAVE. I THINK IT'S A 1969 OR 1970 396 OR 402 2 BOLT MAIN BIG BLOCK STAMPED "HIGH PERFORMANCE PASSENGER" AND THE NUMBER ON THE PASSENGER SIDE THAT WAS STAMPED ON THE BLOCK IS 11027CTW. I AM TRYING TO DETERMINE THE VALUE OF THIS ENGINE (NOT REBUILT) AND ANY ADDITIONAL INFORMATION ABOUT IT. ANY ADVICE WOULD BE GREATLY APPRECIATED.