I had a 440 block with an oversized freeze plug hole....the machine shop picked up on it when they assembled the short block, so they got the next size up and machined it down for a correct fit, then documented it on the bill so if i ever had to replace it, i knew what thay had done.
440's are tough, I've had several overheat with no long term effects, but I've always caught the problem before they ran out of coolant. Thats a good machine shop that will stand behind their work. Good luck.