Toolbert wrote: (clip) The interlock prevents both from being on at the
same time. (clip)
^^^^^^^^^^^
That is a very important requirement, both legally and practically. When I
first set up my generator, I solved the problem by buying a heavy twistlock
connector, and inserting it into the power line between the meter and the
house. I wired a cord with a matching connector, which brought the power
from my generator to the same location. In order to plug the generator into
the house, it was necessary to unplug from the utility. In order to
reconnect to the utility, I had to unplug from the meter. No way could they
be hooked up at the same time, and the plugs were designed to minimize any
possibility of touching a "hot" prong.

Costco, for a while, was selling an overpriced setup, with wattmeters and
several double-throw circuit breakers, which is more convenient. They
evidently didn't sell well, because the price kept dropping. When it got
down to $60 I bought the next to the last one they had, and it working
really well.