Clemson and NC State are more natural fits in the SEC than SoCar and UNC imo. Here's my logic:
Most of the SEC are land-grants with some exceptions: Vandy, Ole Miss, Bama (however Bama did receive a grant of land from the Feds), Oklahoma, Texas, and South Carolina. All the other SEC schools are Morrill Act schools.
Clemson, Virginia Tech, and NC State are also Morrill Act schools.
If you look at the ACC, they're historically mostly liberal arts and private schools: FSU, Louisville, Miami, GT, Duke, UNC, BC, Pitt, UVA, Syracuse and Wake. Add SMU, Notre Dame, and Stanford to that list.
So for SEC currently: 10 LG/MA, 6 other
ACC: 14 other, 4 LG/MA
I propose a trade: Vandy and SC for Clemson and NC State or VT.