I wouldn't worry too much about changing it out. It's nothing spectacular. Definitely old technology.
You can do a lot better now.
What you pick though depends on what you want the nature of the car to be.
To reach their full potential Clevelands need more cam than this.
If you just want a cruiser with an idle like a 53 Merc with a 429 in it, go another route.
Because of the short exhaust system even a mild cam in a Pantera tends to sound radical.
There is lots of debate on what to pick and if you ask 20 people you will get 20 different opinions. None of them are wrong. Just different perspectives.
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