I took the posts off my first corny yesterday. It wasn't that easy, since it seems like they were put on with an impact wrench. None the less, after getting the 7/8" deep socket, and a 12" long 3/4" black iron pipe, I was able to use my 3/8" ratchet set to break them free with a minimum of trouble. I had been struggling with my 7/8" ratcheting box wrench, but couldn't get enough leverage to get them to break free. The standard handle length on my ratchet (6") also wasn't enough. But, put the pipe on there (snug to the head of the wrench) and a couple of taps (hand, no hammer needed) and both came free fast.
Basically, with the pipe, you make a long handled ratchet for dirt cheap (pipe was about $3)... To get a ratchet handle the same length will cost you over $20 (if not $30+)... So for under $10, I had what I need to take the posts off of any corny I get in the future too (I already had the 11/16" deep socket)...
The pipe on the handle is an old trick. Something I picked up from my father many, many years ago. Not sure where he got the idea, but I've seen others use it before, when having one long handle ratchet just doesn't make sense (too limited in it's usefulness)... A couple of different lengths of pipe and you can break almost anything free. Just be sure the ratchet is up to the task. Would really suck to use a 3' long pipe on the tool, only to have the handle snap off from the stress.