Not trying to hijack the thread, but I had a recent incident with the water temp sender wiring. While driving the engine suddenly quit and smoke came from under the dash. After I got it home I pulled the instrument cluster and found the purple temp sending wire at the bulkhead was melted. Very close to a fire. Our old girls have a lot of years behind them now and who knows the condition of the wiring... especially where we cannot see!
You bet. I'm constantly on alert for direct shorts like that. I recently restored a 1977 Dodge truck and decided to omit the bulkhead connectors. I ran all the wiring through a rather large rubber grommet on the firewall.
Just last week I had copious amounts of nasty smelling smoke rolling out from under the dash of this Dart. I found a giant rodent nest that was completely enveloping the 3-speed blower resistor(inside the evaporator box). I got lucky it didn't ignite. Given the time and effort I've put into this project, it would have been a huge bummer!
I also decided to disconnect the battery before leaving the shop.