Thanks for all the tips/info. Yes, I was aware about the limitations on camping in Sumter NF. I'll know more when my guide book arrives, but I believe I read the rule there is "camping in designated campsites only," of which there are few. Anyway, I'll plan accordingly from one night to the next, in that area particularly.
I don't think I'll have to worry about heat in April.
Hey Solemate, not to argue about the driving time, but if it's 76 miles of trail, and roads in between trail heads are always further in distance, if you can do more than 76 miles of mountainous roads in 30 minutes, I think I'll pass on riding with you!