15 inch tire suggestion

Geez 245/60 on the front? I would hazard that you will run into significant rubbing problems with those donuts. My best estimate, using my experiences with my 68 cuda and Australian Valiant Hardtop (read 67-69 Dodge Dart) is that 225/60 15s would be the limit for the front, with 215/60 the better option. 245/60s on the rear might be close in those enclosed rear wheelwells, but do-able with the right backspacing.