65 barracuda need help with rim backspacing

What do you guys think of the Salt Flat Specials from American Racing? They are a two piece wheel and can be ordered with a custom off-set.
I did a little more research on what will fit and I figure that you need a 12mm off-set on the rear wheel on a 64-66 cuda with a standard width A-body axle.
15X8
5.0 backspace (5.25, 5.5 will also work)
12mm off-set

This chart shows what backspace you get with what off-set.