I went with a complete overhaul. So this might be more than you are interested in for an "Upgrade."
- Removed Generator - it was not functioning - so - OUT!
- The space was perfect for 2 @ 260Ah LiFePO4 batteries (520Ah total)
- Installed a 3000 Watt Inverter/Charger - pure sin wave. Has a built-in auto-transfer and a "pass through" as well + Remote
- Installed Shore Power Inlet and Switch (also monitors Reverse Polarity)
- Removed the noisy air conditioner - replaced with a very quiet 8000 BTU Inverter-style ac
- Removed the Battery Combiner (Engine Bay)
- Installed a 420 Amp Alternator and Alternator Protection Device
- Added Bus Bars to the Engine Bay for contemplated upgrades
- Installed a Engine RPM "controller" runs the engine @ 1500 rpm (adjustable) to get to the sweet-spot for charging via,
- The Sterling Battery 2 Battery Charger (200Amp) + Remote
- Installed a 12v Monitoring system (Bluetooth enabled)
- Installed Engine Bay and Alternator temperature monitoring
- Upgraded and installed new wiring to support the entire installation
- Rebuilt Shore Power cord (gained over 7 feet of cord by removing from fixed position)
- Revised wiring to both the ac and microwave. Now each can be run off the inverter
Here is a "notional" summary slide of the wiring effort:
That is more information than you asked for, I'm sure. Hope you find something useful in the list. As an aside, I recall seeing some folks have added a second Tripp-Lite inverter to up the capacity by having two units. I'm not advocating, just remarking that it has been done (AFAIR).
Cheers - Jim