Some folks swear by a 5/16 8 point socket, of coarse I dont have one, so I want to make sure b4 i buy anything. Looking at adjusting the 2nd gear band on a 72ish C6 ... As you know its a square end bolt, I dont own the correct square end socket either, so any direction would be groovy

 

If I remember right I just used a 12 point socket. What I don't remember is whether it was metric or not. Didn't think it mattered much if it was super good fit as it's only 10 ft/lb then back off one and a half turns.

Michael