Wiring additional batteries

Yeah these are Deka batteries they are 98 amp hours each and they weigh 67 lbs aswell. Which is why im concerned about stuffing them all in the compartment under the bed which could throw the balance of the motorohme off on the one side.im basing the 5 amp charging on the c20 I was told most batteries are. The batteries I have are actually 550 CCA so is that safe discharge they are capable of? It won't matter though since my 10 awg is not very long and for the two batteries in the back toolbox I ran 6 awg, they would still be utilizing the 10 awg though to get to the dc fuse panel. Realistically though i cant imagine there would be more than 30 amp draw...if there was the fuse woupd blow in which case i guess i put a 40 amp in since the 10awg should still be fine for this. The only reason I'm saying 5 amps charge each is because I have borrowed a very expensive gel charger and the max it will charge the batteries in auto is 6 amps which tapers to about 3 or 4 once it reaches full charge per battery.