Get either the repro iron MW heads or iron Stage V heads, grind the casting numbers off and braze/weld/epoxy the correct casting number on, and voila. Stage V's look just like a 452 head on the outside and I'm about 90% sure the repro Max Wedge head is the same way.

It's not the rules, it's the INTERPRETATION of the rules, and if anyone thinks that hasn't ever been done, and casting numbers have never been changed....well....

The rules say the head has to have the correct casting number. The rules do not say the heads have to BE that casting number, or have started life as that casting number. So as long as they "have" the number I have to assume the above procedure would be legal or at least overlooked.