Liquid Wrench over night may or may not have helped. Also if you angle a large flat head right under a screw aiming from the bottom with the goal of prying it out and then beat the crap out of it for a few minutes the thing finally came off!! Air tools and rust converter and I'll be putting it...
I'm searching for an answer myself, same problem here in CT! Thing will not budge and looks as if it may crumble apart before it comes off. Last attempt will be a torch, will let you know of the results.
