On my generator that was stolen I had added an external charging plug. I never had to use it, so I'll not bother with the replacement genny.
I think your plan is good, so long as you use an appropriate connector. Bare wires are not acceptable (can you say catastrophic short?).
Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp-hours of Telcom jars, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.