Wow, Incredible Hulk industrial batteries you have there. The specs say they are 415 lbs each. And 925 Ah!
https://www.trojanbattery.com/pdf/datasheets/IND17-6V_TrojanRE_Data_Sheets.pdf
If it was mine I would completely rewire the system, tidy it up, and do a equalizing charge.
I don’t now anything about Simplphi so no comment except I am also wary of complex internal BMS systems that come with drop-in-batteries. It seems to me Lithum make sense for mobile systems where size and weight are critical. If I was buying for a fixed system I would be considering nickel iron batteries.
How many years have you had the Trojans?