Wiring Multiple Batteries

I need some help on how to properly wire 4 batteries (1 main battery under the hood and 3 batteries in the trunk for the amplifiers) and how to wire the amplifiers to the batteries. My total system RMS will be 6250. I will have 5 amplifiers. 2 for my subs, each amp being 2500 RMS. 3 for my speakers, each amp being 500 RMS(125RMS per channel). I was thinking having one battery for each subwoofer amp, and one battery for the 3 speaker amps. I plan on using bus bars. Would this be sufficient? I dont know where to start with wiring the main battery to the 3 batteries in the trunk. Do I.run 3 power cables from the main battery to the positive terminal of each of the 3 batteries in the trunk? Do I do the same with the ground wire? Then do I run another power cable from each battery in the trunk to the buss bar, then a power cable from the bus bar to each amp? I am totally lost on how to do this properly. If.anyone can explain to me in detail the proper way to wire this.set-up, it would be bery much appreciated!! Also, I plan on getting a mechman alternator. Will 270A be enough? For batteries I plan on going with XS. What models of XS batteries do you reccomend for my set up, both for the main under the hood battery and 3 batteries in the trunk for the amplifiers.

You will have multiple runs from the front battery to the rear. Minimum of 2, personally I would do 4 (2 positive, 2 negative, 1 set from battery and the other set from alternator.) It is best to have all batteries wired together, if you are using a buss bar then you are set. A lot of people like to wire all positive wires to amps from one side of the battery bank, then all grounds from the other side of the battery bank. A 270 amp alt will be okay, if you plan on playing or long durations you may need a second alt.

If I choose to run 2 pos. Cables and 2 grnd. Cables from the main battery to the batteries in the trunk, and do not use buss bars, should i connect 1 pos. Cable and 1 grnd cable to two of the batteries in the trunk, or would i connect both pos. and grnd. Cables to the first battery and then proceed to wire the batteries in parallel