Iowa (from 1986):

LSU (from 1982):

Up until Wisconsin switched number fonts in 2016, they more-or-less have looked like this since the early 90s:

Auburn (mid 80s)

Georgia (1982)

USC has made only two changes in the past--a one year helmet in the mid 90s that didn't go over well and shoulder stripes to shoulder in insert circa 2003: