Think of it this way, you are using a 7 inch wide rim. The numbers for offset represent inches available in the total width of the rim and so will always equal 7 for us. A 4+3 offset pushes the mounting position of the wheel so that there is only 4 inches from mounting point to exterior sidewall and 3 inches from mounting point to interior sidewall, thus pushing the width of the vehicle out 1 inch for each wheel relative to a 5+2. A 5+2 offset puts the mounting point for the wheel 5 inches from exterior sidewall and 2 inches from interior sidewall, which is a total of 2 inches more narrow than a 4+3.
I have 5+2 offset wheels WITH 1 inch spacers, which puts my total width equal to the width i would have with 4+3 wheels and no spacers.
With my rig at 57 inches wide, I had mud flying all over the place until I got the Mudbuster fenders. They caught so much mud on my last trip that would have otherwise ended up in my face. If the tires are the widest part of the P5, you will throw mud into the cab.