should put everything in the stock locations so no added wheel offset. I had this kit on my 65 I had. I had to get 15" rims, 7" wide, 4.75" backspace. I did have lowering springs and disc brakes that made the hub sit out about 5/8" more than stock would have been.
As Miles stated there’s no real difference in wheel mounting location with the CPP Mini subframe kit. If however you intentionally run an offset brake kit and an offset wheel, things might get interesting..
Otherwise, 7” is pretty much the standard width allowable up front under most circumstances.. I’ve got some 17 & 18x8 wheels i test fit on my 64 a couple of years ago with stock suspension and later with the CPP kit installed. These wheels have 5.25” of backspace and were on the coil spring when I tested them, but I also had my lower control arms cambered all the way out.. I later backed off the camber setting to a more neutral state but I haven’t tried the wheels again.. I might need to do some more testing..