Question about replacing 15x7 wheels with 15x8

i have a 73 dodge dart sport and i just bought a set of 15x8 american racing outlaw rims for it.. i am trying to find the right size tires to put on the rims.. i dont want them to rub.. my main concern is the front wheels.. please any help would be great.. i just dont want to buy 4 tires and they not work.. the dart is stock, never modified..
thanks!