^A C and D Modified were classified together at VIR; the combined class was won by Roger Penske in a DM-class Cooper Monaco. The highest-finishing CM car was John Todd's Warwick GT350-Buick in 3rd.
^B D Modified were classified with C Modified at Bridgehampton.
^C C and D Modified were classified together at Lime Rock; the combined class was won by Roger Penske in a DM-class Cooper Monaco. The highest-finishing CM car was Bob Colombosian's Buick-Mustang in 2nd.
^D E Modified were classified with D Modified at Lake Garnett.
^E C, D, and E Modified were classified together at Thompson; the combined class was won by Bob Holbert in an EM-class Porsche 718 RS 61. There were no DM cars; the highest-finishing CM car was Don Adams' Lister-Jaguar in 2nd.