To finish of the install I secured the batteries with aluminum L channel and placed a carpeted “lid” on to protect the batteries and allow continued use of the closet. I was a little rushed to close off/protect the inverter and other components but I like the final solution. I used a thick piece of acrylic sheet to protect the components while allowing visual inspection. I was going to make a mechanism to allow opening of the panel but instead cut holes to allow access to the important switches and breakers. There are only a few screws so removing the whole panel will not be much trouble. I also left gaps at the top of most spaces and installed two four inch vents at the top of the space to allow heat to leave while the opening under the fireplace will allow fresh cooler air in.

Acrylic panel installed with access holes
Battery compartment. I may seal the current gap it has.
Access for solar charge controller switch and breaker
Access to inverter switch and GFCI breaker
I skipped the hole for this panel as of now. I don’t think I will have a need to “turn off” individual panels often.
Vents to allow hot air out. I can add some 12v fans if necessary, for now I will see how effective convection is.