I don't think I've ever seen a crank that was machined for a customer(rather than for shop use) marked, other than a paper tag attached. Big rebuilders always attach a metal tag to the block somewhere, usually riveted on. On my current engine, it had no tag, no markings at all on the crank or block. Pistons stamped .040, bearing shells marked on the back, .020, probably a rebuild in the past at an independent shop. Like I've always done, tear down, measure, send crank and/or block to the machine shop, and probably two different shops. Local guy did boring, cranks went to a bigger shop, or just pick up and exchange crank at a local engine rebuilder. I then picked up and assembled, usually after a hone in my place to my liking. I usually did the valves but had the head surfaced at a machine shop.