People are really overreaching here. Aside from Vandy (the best SEC school academically) and Florida (not hardcore southern), I don't see Hillary winning any other SEC county. The SEC students are not liberal; they lean much more to the right, and I know for a fact that Trump is VERY popular on SEC campuses. Do not be surprised to see a sea of red MAGA hats at SEC football games this fall.
As a proud member of the SEC, I could promise that, between all 14 schools, there are far more conservatives than liberals. Florida, Mizzou, and Vandy would be the only ones with even competitive overall student bodies but even these are pretty 50-50, I would imagine. Maybe there are enough Johnson voters and minorities to put UGA into play as well. But, as for counties, he'll probably lose Davidson, Richland, Clarke, and Alachua.