[Ronbo]

I can't really agree about the comments concerning ampmeters, idealy both it and a voltmeter give you a true look at the vehicle electrical system.

Voltmeters cannot accurately indicate alternator output or system loading, period. If your concerned about high current levels under the dash, worry about that Lucas ignition switch.

As far as a 100A swap out, upgrade your ampmeter and verify your lines between the alt - meter - battery are at least 6ga fine strand wire. Obviously someone who actually understands vehicle electrics is your best insurance against dash fires. Your average mechanic who thinks he understands it is the #1 cause of mishaps.

I've got almost 30yrs as a electronic technican so I'm well aware of car mechanics electrical work, not to mention what the car mfg's sometimes do (especially Ford).

Actually I should mention why the fires occur, a condition called "thermal runaway" occurs in overloaded electrical components: over current causes heat, the heat raises the resistance of the component causing even more power to be dissipated resulting in a cycle which eventually reaches the flash point in the insulating materials - fire. Think of super conductors, they have to be cooled to sub-zero tempatures to work. Scientists are still striving for the ellusive room temp superconductor.