Charging my Interstate wet cells

Problem: Winter solstice. Tree shade. Clouds. Seagull souvenirs. Let the main genset hammer what it can into the batteries then when it quits and takes its ball and goes home at 14.2 the Megawatt is great down to around 6-7 amps per battery. After that it ain't worth running the generator. It's that magic 20-40 amps the perverter cannot touch is where the Mega shines. When Quicksilver starts there is a 15-second delay until 21-horsepower drags the Cummins down. 400 amps of 28 volts does not screw around. It would be nice to have a 200 amp Megawatt but oh well. Balancing solar and generator is an art form that can only be correctly conducted by the owner. When I had an aircraft carrier deck load of panels on the 33' trailer. I got away with a 200 amp charge rate for a hour near sunrise. At dusk the batteries were at 100%...in no clouds Baja California.