My 30MM socket
Made my own 30MM socket, like others have, and thought I'd share my process. Just used what I had.
Bought the socket from Napa, and took my band saw to it. I made about 6 cuts over the distance I guessed I'd need (coincidently, the width of the grinding wheel on my bench grinder), and just cut the thickness of the blade. Beat a chissel in between each cut until the remaining metal popped out. Then put it to the grinder to clean it up. I used a breaker bar to hold the socket securely while in the band saw and on the grinder. That kept it from spinning on me.
I also had a 12 MM allen in a socket, which works well for removing that piece of the puzzel. You can pound the allen portion out of the socket for installation.
I used a ratcheting box end for the install, which worked really well because you can chase the cut around during torque, rather than removing a standard allen and resetting (see photos).
All in all, worked well, and not a scientific process.