That tongue was much longer then needed and I just put a pin through at the appropriate place.
The straighter the shaft, the better. Almost perfectly straight is obviously the best.
I had a friend with a crooked arrangement and his lights always flickered. I don't know if this was the reason or not. I can't believe that it didn't drive him crazy!
As far as the 3ph goes. You want to stream line the whole operation as much as possible. I had a 12 volt florescent light mounted in the middle of the garage connected to a 12 volt alarm panel battery that was always charged. It was controlled by a clockwork type switch with a green flashing LED beside it, so I can find it in the dark. Nothing like trying to attach a 3ph unit, in a crowded messy shop with just a flash light!
And then, the power comes back on.
The chicken barn where I got my genset, had a hole in the wall for the pto shaft. The genset was just sitting on some blocks!