wondering if these wheels will fit my dart

They are summit wheels.I dont care if i have to move the rear springs in some,i just dont want to have to mini tub the car right now.Do i need the 4.50 backspace wheels,or 5.5 backspace wheel?Its a 71 dart,with a body 8.75,and resplined big bolt axles and 10 inch drums. http://www.summitracing.com/parts/SUM-521-5865PS/ http://www.summitracing.com/parts/SUM-521-5866PS/ oh,and i want to run the 4 inchers on the front.Is anybody else running these wheels on there darts?What size did ya get,and what size tires are ya running?