and the specific rule required the visiting team to wear white in all games. This was a change from custom for schools like LSU and Georgia Tech, which had worn white at home for years. (GT did wear gold jerseys at home and on the road versus ND from 1968-1970; ND wore white in the 1969 road game and blue at home in 1968 and 1970. GT wore white at home vs. ND in 1967, 1974, 1976, 1978, and 1980.)
Before 1983, I doubt there was a rule in place, unless it said the teams' jerseys had to sufficiently contrast. USC and UCLA always had worn their "home" jerseys when they played one another. UCLA also frequently wore their powder blues when other opponents wore their "home" colors -- e.g., against Ohio State both in the 1975 regular season in LA and the 1976 Rose Bowl. And the last time I recall a visiting team at ND wearing "home" jerseys was 1978, when Tennessee wore orange and lost to green-clad ND.
The following year in Knoxville, ND wore white (and got shellacked in Devine's worst defeat as ND coach).
After the 1980 game at GT (a depressing 3-3 tie), ND didn't wear "home" jerseys on the road again until 1997 at LSU, the year the rule was changed to permit the home team to wear white if the visitors consented.