The inverter install is as above
Check Morningstar web site for specifics
The Transfer switch aka DPDT 30amp relay came from a defective 50amp transfer switch out of a old inverter / charger - Darn thing had 12 of these very nice heavy duty DPDT relays in it.
Obtained the relay coil power from a plug in brick 115ac to 12VDC. The AC input to the brick comes directly from inverter. The DPDT connections open both White aka neutral and Black aka hot lines after the breaker and before the recp. Really very simple install and does for us exactly what it was inteneded to do.