New alternator and battery drive 10 miles wont start battery dead

CAUTION: NEVER DISCONNECT THE BATTERY TERMINALS WITH THE ENGINE RUNNING. This will instantly destroy the 6-way rectifier/voltage regulator.

Check that the Generator Failure light comes on and stays on with key on and engine off. N.G., verify your connections on the back of the generator. This circuit must function or the generator will never charge the battery. If this indicator circuit is miswired (the small spade connector is disconnected, plugged into the wrong connection or otherwise nerfed) the voltage regulator open-circuits the field (rotor) windings and in turn, the generator will never charge and freewheel. Check the circuit from the connector on the back of the generator all the way to the dash, verifying the light bulb in the dash is good. My trick is to wire in a small 3 watt bulb (or a continuity light) in series with the circuit under the hood. Turn the key on to KP II and verify it lights up.

Others: Check ground from generator to engine. This is usually a large blue cable that ties off onto a bracket near the air valve. Check ground from engine to body. Check ground from battery to body to engine. Must read less than 1 ohm on your megger.