Very nice! Sidebox idea looks familiar.
Mind showing us the GC battery setup?
This is the general layout. I built a plywood box with a removable shelf for the inverter and sprayed it all with rhino type liner. The plywood box keeps the generator side considerably cooler when in the sun and is convenient for screwing wires and the like to it. I figure that the lower temp is good for the batteries as well.
On the back wall is the Nocco 10 amp charger and the MPPT solar controller. I fabbed a removable plywood front tray to mount the master switch, the solar remote panel and the breaker panel. For wiring, I used 4 gauge for the batteries, master switch and busman high-current fuse. I used 8 gauge for the 66L. Snowmaster Expedition Fridge/Freezer. The GC2 batteries are wired in series and sit in a Nocco dual battery box. Conveniently, the battery box fits the Smittybilt generator tray as if it was made for it. Each compartment has a 10 gauge XT90 plug for 12v. power. Each compartment also has LED lighting mounted on the roof. I can run the fridge at 4c. and the freezer at -10c. for about a week with on-board power before I need to recharge. It takes about 3.5 hours to fully recharge using solar.
Other than the 2 shorepower and 1 solar input connector, there are no holes drilled into the box.
Silverback.... the side boxes are your idea
Top shelf looking to the rear (need to work on the cable management).
Front master shorepower and solar panel input. The boxes on top are USB and 12v. portable power boxes I made from electronics hobby boxes. I made a couple of 10 foot extension cables and can run them into both tents.
Shorepower and solar panel input cables inside.
Solar, aux extension cable and portable power boxes.
Rear fridge 120v shorepower