Its a big wall of text and odd abbreviations for everything. Let me venture back in.
12.8V x 300Ah = 3840Wh
What watt hours are you talking about recording? The number produced in a day from solar?
If so then your daily solar (with no loads) should charge about 50% of your battery.
(2310Wh/ 3840Wh) = 60% if operating at 100% efficiency
The wire size depends on the volts, amps and distance. I cannot find how big your new inverter is going to be.
8Awg is small for a 100A SCC to battery.
900W solar / 14V charging = 64A so 8AWG wire not big enough. If you have enough, double it up.
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How are you figuring 10 hours of solar?
Its more like 3.5h in December
1500W x 3.5h = 5250Wh
www.solarelectricityhandbook.com
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