Bbc -- crank info
 

I'm trying to identify a Big Block Chevy steel crankshaft. It's supposed to be a 4.25 external piece. I can't find any ID numbers or company name engraved anywhere. The only numbers i found are painted or stenciled on one end. They read M3 -- 99 -- 3 -- 16 -- 3CW. Can anyone please help, thanks.