Including Captains Byron Spruell and Chuck Lanza. Also starting OL Tom Freeman and Tom Rehder. We would have been completely screwed without them. They were named players of the game for the USC game. Fullback Pernell Taylor was a 5th year as well. Another 5th year in 1987 was starting corner Marv Spence. Another was our starting NT Mike Griffin. Alonzo Jefferson was also back for his 5th. Alvin Miller could have come back as well but opted not to given his knee injuries.
In 1986, Milt Jackson and starting OG Shawn Heffern were both 5th years. DT Wally Kleine was a 5th as well, before being a first round pick. FB Tom Monahan was also granted an extra year as was MLB Ron Weissenhofer. Could think of a lot more examples if I had the time.
Plenty of guys didn't play in 1987 in order to preserve a 5th, with Zorich at the top of the list. He was pretty huge by the end of 1987 and could have helped. Holtz would empty the bench in blow out wins against No. 10 Alabama and eventual Rose Bowl Champs MSU, and the order went that "everybody plays" including every walkon. However, this excluded freshman Zorich, Darryl Wodecki, Winston Sandri, Brian Shannon (hurt as well), George Marshall, Ryan Mihalko, Greg Davis, Bob Dahl, Mike Callan, Norm Ballentine and Joe Allen.
There is no question that we redshirted back in the day and ever since. Stories to the contrary are the usual mindless "the game has change" bullshit.
Edit: I should add three more that didn't play that year as freshman: Bobby Carpenter, Pierre Martin, and Brian Dower. Didn't think of them initially because they transferred out. David Rosenberg didn't play either, but he was injured as well. Approximately half the freshman class was kept out.