i need to replace my Goodyear ST tires on my 71 cutlass as shown. the car has wheels from a 69 442 (14x6 i think). i was thinking about ordering from coker a set of SS1 15x7 along with the BFG 255/60/15 tires. is there a better combination for a weekend cruiser? what are the advantages/disadvantages of the 15x8 wheel on the same tire? thanks in advance...