new engine for my truck

[67slammer]

a guy i work with has been trying to sell me a 327 for months and i finally got him to sell it for $500 he told me that it was bored 20 over with 11.5 to 1 forged flat to piston with h beam rods and steel crank all balanced, plus has roller cam lifters and rockers, it also came with edelbrock intake, holley 850 double pump carb and hooker super comp headers. i think he must have needed a fix or something i got all the receits from the parts and the machine shop. when i got home i looked up the casting numbers on the block 3932386 and found out the block came out of a 69 camero. the only thing i cant find is what the casting numbers to the right are a m inside a square and a 4 if you guys know please get back to me. the engine is a little over kill for my truck but i just could not pass it up