Hi Solar, I had a thought, rather than run one giant inverter, it may be better to split the loads and run a couple or more smaller inverters.
It seems that once we have just one big inverter and it blows up then things get complicated.
If you were to say use one inverter for lighting, and two for power, ( split the power outlets in the house over two or more circuits) then redundancy allows for quick swaps when needed.
I am having a good run so far with the 8010 based aliexpress boards. I have three now. One with a rewound powerjack transformer form an 8kw powerjack and two with transformers from an 8kw powerjack that had two transformers.
So far they are working well, nice clean sinewaves and no failures.
Setting them up requires a variable power supply to set low voltage cutouts , high voltage cutouts and overload but that is not too hard.
Then just following Ozs stuff on getting rid of the chip off the 8010 board. After that all seems good.
I hope that your retirement goes well and that the system you have set up runs for many trouble free years.
Oh , I don't have grid power so there are no problems with changeover here.
Glad you got yours sorted
Pete