How to identify 0331 or TUPY head

Hi everyone, I've searched for this and haven't really found any good answer. I have an '01 tj with the 4.0 engine. I would like to find out how to identify what head my engine has on it. I've read that the heads labeled 0331 are prone to cracking and that they were changed to a head labeled

How to identify 0331 or TUPY head

the 0331 head thread (help out if you have one!) - Page 5 - Jeep

Avoiding a Cracked Head - Jeep Cherokee Forum

the 0331 head thread (help out if you have one!) - Page 5 - Jeep

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