Magnum Heads

I don't know if there's a big differance in castings. I used the 466 casting. I was told magnum heads are the thinnest and weakest of any Mopar casting ever made. Just because your's are ok now does not mean they won't crack in the future.
Then what do you do, try and find a used head to match your good one and have it remachined. Then maybe the other one will crack. You''ll have a lot of money in a set of junkyard heads. More than a new set will cost you. That's the conclusion I came to. I see other members have had good luck with used heads and I'm glad, I just didn't want to take that chance.
You can get a nice set of J heads for a lot less money invested, and the engines there bolted on run well. Just my 2 cents.