'''++Zachary Devall++''' we would have to see what all of this melting looks like. Post some good pictures of the damage with your QUESTION. [guide|21499]
You can get replacement battery terminals [https://www.classicindustries.com/product/all-years/pontiac/firebird/parts/10626.html?gclid=EAIaIQobChMItNDK6bLp6wIVAtvACh3zCwfsEAQYBCABEgIFG_D_BwE|like these] instead of replacing the full harness.