15x 7 cop wheels fit on stock 67 Dart?

I tried to get a set of 15X7 steelies under my 69 Dart and they wouldn't go using 245/60/15's (they went on but were paper close to the wheel lip). I ordered a set of custom 15X7 steelies from Summit with 5" of backspacing going to be installing the axles etc next week hopefully my measurements were right.