Interesting question. Personally I wouldn't spend the time to tear down a set of cast iron heads and port them but time vs. money is something that everyone has to sort out for themselves. A big block A body car is nose heavy anyway so why not find a used set of aluminum heads to go on there? You might find some used Stealth heads for roughly the same cost that it would take to rebuild and port a set of cast iron heads.

Of course, if you're doing the heads as a shop class project then time vs. money doesn't really matter. In that case it is just an education project so go after it. If you need another set of 452 heads in case those get messed up they are easy to find. I have a few cores sitting in my shop that I'll never use and I'm sure others do as well.