Size backing plate?

[frank10]

My kit came with the 6" backing plate. Should I look into a smaller backing plate to cover smaller areas of my truck, like the 3.75" backing plate?

[ScottB]

the general consensus is to use a backing plate one size smaller than the pads being used. So if you plan on using 4 inch pads in smaller areas, then the smaller backing plate is a good idea.