You want to take power off the nearest and the farthest battery
That means, use the positive post on battery
number one, and the negative post of battery number four.
You do NOT want to take power off of just one pair if you can help it.
Be very sure that you are using high quality, large cabling between the batteries. I prefer AWG 1/0 or larger, with professionally installed lugs. All connections must be very clean and very tight.
Wing nuts are a no-no. You can't get them tight enough.