[rotorwrench]

Poor connections and wire that is too small a gauge for the amperage requirements can be problematic. This adds up the resistance in the circuit. Resistance creates heat just like a resistor does. A lot of the aftermarket reproduction replacement electrical parts don't hold a candle to the original equipment. Headlamp connectors and light switches may not be up to the task that the originals performed and same for any connectors in the system.

It's a good idea to have circuit protection of any kind. A lot of cars burned down back in the day. The automatic reset feature can get you home sometimes but it has to be the correct amp rating for the size of the wire gauge in the system. The wire gauge also has to be correct for the application. If the auto reset breakers give trouble, try a new one but be certain it is correct for the application.