Thanks for all the great suggestions everyone. Initially I plan to go with the shore power route suggested by some. The challenge I am finding as mentioned above is with disabling the converter. Doesn't appear to have any type of switch and I don't have direct access to the backside of it. I believe all the breakers in the pic below are to the AC circuits on the output of the converter. Its most likely hardwired to AC on the input side.
I understand the point of disabling the converter is to not charge the batteries off the inverter AC power. Wondering if using my battery cutoff switch would accomplish the same (or close to it). The converter would still be powered but nothing to charge at that point. Power draw may be minimal but would need to test to verify.
