https://www.battsys.com/amfilerating/file/download/file_id/8/Should work. Having four 6s at 77lbs each could be handy. I have a 250AH 12v AGM in 8D size which I needed help with to install it is so heavy.
The charging specs are unclear to me. Usually with AGMs you charge them at a minimum of 20% AH rate, so at least 50 amps for 250, and at some max rate, usually about 30% (except Lifeline you can do more %). This shows cyclical recharge at 0.15 to 0.1 as rate, but for equalizing (see Float maintenance guide at bottom) 0.3 is given. It also says 68 amps max or 27%. Some other AGMs also use 27%. (136 amps on the 500)
If mine, I would recharge the 500AH at minimum 100 amps or more to a max of 150 amps. To do that, you would need one of those inverter/chargers that have those amps. To power a power factor corrected charger such as in those inverter/chargers at 150amps you will need a 3000w generator.
Your typical RV converter will undercharge those batteries with its low amps and incorrect charging profile.
Be sure to fully recharge to 0.5 amps/100AH -- so taper down to 2.5 amps at 14.6v on the Trimetric (you must have an ammeter of some kind to see that figure --part of the AGM set-up) before dropping to 13.6 Float.
Important to wire the four in series/parallel with the load/charging with pos on one pair and neg on the other pair. DO NOT let the dealer wire them up with a "downstream" pair like he probably will.
