In my (admittedly unqualified) opinion, the common lower rear chassis braces offered by Precision ProFormance and others will do the trick by acting as a very large washer to distribute the load. The Pantera Parts Connection brace is not built the same way, and so I do not think it will work.
For a definitive view on this, you should contact Mike Drew and/or Kirk Evans, who actually cut frame rails apart to compare the internal reinforcement in earlier cars to the absence of it in later ones.
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