what size light bulbs

[TomoHawk]

Good point(s) Mike-

In trickle-charger circuits, we sometimes use small incandescent bulbs to limit the current, so in essense the bulb is working like a resistor or a high-resistance wire, which is what most of us deal with.

[MikeW]

So, couldn't "butchered" wiring cause something like this to occur? Where the filiment in the bulb would act like the fuse?

Nope. Not that I can think of. Only higher voltage would burn out the bulb. Think about a flash light with weak (low voltage) batteries. It would be very dim. Too much voltage would make the flashlight bright and would burn out the bulb. I suppose if your alternator were putting out too much voltage or the voltage regulator wasn't working right you could burn out the bulbs but nothing in the wiring itself could cause this.

The one example that comes to mind is the S/S Clutch hose on blitzcraig's car that kept melting and burning due to grounding issues.

That happened because the braided S/S clutch hose had little resistance. There would be next to no resistance from the battery through the cable down to the starter solenoid and if that cable instead touched the clutch hose a lot of amperage would flow through the clutch hose (trying to find the least resistance to ground) and it would burn it up the hose.