Question How to provide power to Subpanel with Solar using 12000XP

Hi All,

I've hit the wall.  I've watched many YouTube vids and read through 3 of the wiring diagrams from EG4 for the Gridboss and 12000XP/6000XP etc, but can't find out how to  provide power to my existing subpanel in my garage, if it's even possible without a critical loads panel.

I would prefer to not use a critical loads panel.  I would like the 12000XP to feed my Subpanel power, the issue is I also have a 40 amp breaker in this panel that is my current Solar system feeding back to the grid.  I do not want to feed power back to the grid from the Inverter.

A perfect setup would be from my 12000XP to the subpanel, and if the inverter dies or quits, then power to the subpanel would be fed from the grid.

On an off topic, I would like to be able to bypass the inverter altogether, should it fail to work and need to be repaired, I suppose I would need a manual transfer switch to  direct power from the grid directly to the panel (as it is now).

I'll include my subpanel picture, it's nothing special, 100 amp power, with a bunch of breakers, and again one of those double pole breakers is my Solar feeding back to PGE NEM2.

Thank you