What size wheels and tires

I'm converting to disc brakes on 66 Barracuda using 75 dart slider disc setup. What size rims and tires did you use for this swap? Looking to replace present 195/70/14 (sbp)with larger tires that will fit the new setup(bbp). I have 15"/5.5 Ralley, 14"/6.0 Ralley and American Racing Outlaw 15"/7 sets available. Want to know what size rim and tire that will fit.
Thanks