Quick Backspacing Question

Yes the back half of my 66 Dart has not been altered at all. It has caltrac 1 inch lower mono leafs and bars in the stock location. As far as wheel wells go I think they are pretty close in size with nod to the newer Darts for the bigger wheel wells. I have a buddy with a 69 Dart with 275-60-15 on 7" wheels with 4 3/8 back spacing but his car sits slightly higher then stock, those will not fit my dart. As far as the bigger bolt pattern goes the inexpensive way to do it is to have the stock axles and brake drums redrilled or you would have to buy new axles. Price of both very by machine shop or manufacturer. Axles would run about 3to4 hundred, redrilling should run a hundred or less. The front end would be the cost of a big bolt pattern disc brake swap, but I have seen cars with the front hubs and drums drilled out.