amp power wiring with 2 factory batteries

wondering the correct method to install power wiring in a 2006 dodge ram 2500 diesel with 2 factory batteries. to the best of my knowledge the batteries are not isolated from one another. my concern is will one battery see more of a load wired one way then another. is there any way to connect the amp power wiring so that both batteries have the same load on them?nice...

Are they are in parallel and NOT switched between parallel and series (ie, 12V to 24V)?

Your batteries are wired in parallel.  The wire that conects the 2 batteries together is large enough that both batteries will power the amp equally.  (For all intentional purposes)  Just connect it to the one that is on the side of the vehicle that you run the power wire through the firewall.

That's good.... I hate seeing people grad 12V from one battery in a 24V system, or rewire not realising a parallel my be series for cranking.... They should be wired so that the +12 outlet is from one monoblock (battery), and the ground is from the negative of the OTHER.    I ideally one battery should be disconnected from the other when not being charged nor heavily used, but I doubt most do nor care...

they are in parallel 12 volts.nice...

Good. The only load difference will be different path resistances. Hence why parallel batteries should supply the +ve from one, and -ve (ground) from the other. For charging it won't make significant difference (assuming they have enough time to recharge).