Any battery that has a rating of CCA or MCA is a dual purpose (hybrid) battery and is not a "TRUE" deep cycle battery. So, if you are interested in the max output for dry-camping you should look at batteries that are "TRUE" deep cycle batteries.
For dry camping you want the batteries with the biggest Amp Hour rating. You could use your existing size 24 batteries, not sure if they are any good, as I do not know their history (let the voltage drop below 12VDC... below 10.5VDC (actual dead battery). how many times... Age of the batteries... maintained proper water levels... kept at full charge.... sitting at less than full charge... The list of things goes on.
How long do you dry camp?
Do you monitor your battery(s) voltage?
Do you shut them down if you drop below 12VDC? (battery 50% rule)
Ever run the battery(s) down to a point where things did not work normal?
Do you use an inverter? For what?
Battery connections tight?
Don
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RVing with SOLAR