360 crate motor????????not sure

The Mopar LA crate engines had an M-1 dual plane intake (300hp) and M-1 single plane (360hp). Heads were 308 (maybe 576) but casting #'s were on the underside of one of the pairs of intake ports. Pistons were flattops with valve reliefs. But as old as the original crates are, this one could be anything. If it's running well, I wouldn't be in a hurry to disassemble it.