Underdash Harness bunt up

Is the bulkhead connector melted too on the inside or outside? I've seen harnesses like this that were hot over a long period of time. If those connections were corroded could it result in a level of resistance that would cause this damage? Those bulkhead connectors are a weak link in the system - Chrylser never built them with 50 years of use in mind so the corrosion is slow and progressive. Hardly anybody pulls them apart before they have problems and cleans the terminals and repacks with di-electric grease to keep them functioning properly.