A. It depends upon what the specificaitons are of the RV batteries that you plan to use with the replacement.
Some RV batteries specify to be floated at 13.5 volts to 13.8 volts. A lot of common 3-stage and 4-stage RV converter-chargers use 13.2 volts as their floating voltage. So be aware of all this when you replace your 6336.
B. Another consideration is if you plan on sometimes powering a new converter-charger with a generator during drycamping, make sure that the generator is large enough wattage capacity so as to be able to fully power whatever size converter-charger you get at whatever amps it will try to deliver to your RV batteries at the occasional times when they may have been discharged down a lot.