Need Voltage Regulator Help, Please

Let me reiterate again what I said about the 42 year old wiring and the fact it might have had a 50 amp. alternator out of the factory!

Is the new 100 amp unit a square back alternator like the newer 1971 up units? If it's wired in the field side like the origional 1968 unit it will work. If it's the newer "Square Back" you might have to ground one of the field terminals to get it to work.