charging system trouble

On my 64 dart wagon with a small block and m/p electronic ignition, Im getting 15 1/2 volts at the battery. Over 16 volts when the lights are on. The battery leaks a little water around the top if I run the car for a while (20 minutes). The leaking was much worse before I installed a new voltage regulator. Still, im getting 15 1/2 volts at the battery when running. Is This too much?
The instructions for the electronic ignition says I should have no less than 12.5 volts at the ballast resistor. Im getting 12.3.
The alternator im using was given to me by a friend. It is a 2 terminal type.
All my wiring seems to be correct.
Any suggestions would be greatly appreciated. Thanks.