Lots of possibilities here, but wires that get hot are never good. Wires should run cool right up to the point fuses and/or fusible links blow. When it comes to bad wiring and/or connection points, cut out and replace anything questionable. If you're missing fusible links, then put them back in the system. When doing this type of work using the correct tools and materials is important. If you don't have them and/or don't want to buy them, take the van to an auto electric shop & pay them to do it.

Typically when all the dash lights come on it means you have a bad alternator or there's a problem with the alternator wire harness. If your alternator is good, then I'd suggest focusing on the harness. The little wires that connect via the round plug get brittle and break. It's not unusual for them to look good (insulation still intact) but still be broken inside. Harnesses are no longer available, but they sell repair parts on eBay and other places. We've discussed this a couple times here and I'm sure there's threads with links to these parts. Using the terms "alternator harness" should get you to those threads. Good luck. Tim