Installed the remaining battery bars and cables. Secured the cables to each other and the battery boxes to prevent flexing at the ring terminals where they are more likely to break.
After an email to the factory I turned the engine tach sensor in 1/4 turn which means it's now 1/2 turn out from touching. Since the sensor threads are 18 TPI this should be about a .025 - .030" gap. Temporarily attached the tach and spun the engine up with the starter and wala, it now works. The tach starts reading at about 5000 RPM and stops once the revs drop below about 2000 RPM. Posted a short video of this test on youtube at the link below: