Bicycle Mechanics - Stuck Left Side Cup, Advice Needed

I picked up a Hard Rock, about 6 or 7 years old. It has an aluminum frame. The bottom bracket was wobbling badly when I bought it. I removed the cranks and could not remove the left side cup. The right side drive cup, the one that usually takes a little coaxing, was tight, but came off OK. The BB is not a cartridge type, but the older style, with bearings in a metal container. The lock ring came off no problem. I was able to move the left cup about one turn, no more. NO, I don't believe it is cross-threaded. I say that because it does not appear cross-threaded and the lock ring comes up flush against the frame. By the way, the cup surface is destroyed, the previous owner ran it while it wobbled and beat the crap out of it, destroyed the bearing retainer and scored the cup badly. So I'm not trying to save it, but I don't want to damage the frame. The cup is a later design and I'm using a Park BBT-2 tool attached to an 18" breaker bar. As I said before, I coaxed it to turn about one turn, maybe a little less, but that's it. I tried a vice-grips, no help. I tried liquid wrench but that didn't help either. Short of taking it to the LBS, any ideas how to remove this thing?

If you're referring to the fixed cup on a cup and cone type bottom bracket, try this link http://sheldonbrown.com/tooltips/bbcups.html about 2/3 of the way down. Good method if you're having trouble getting a purchase on the flats.

If you're referring to the fixed cup on a cup and cone type bottom bracket, try this link http://sheldonbrown.com/tooltips/bbcups.html about 2/3 of the way down. Good method if you're having trouble getting a purchase on the flats.
No, I'm referring to the left side, adjustable cup, the one with the lock ring. But thanks for the response. I read Sheldon Brown's link and it's no help because the adjustable cup is the newer, Shimano type design, a spanner won't work.
Thanks for responding it is appreciated.

Someone a while back mentioned that ammonia is utilized rather than liquid wrench in easing aluminum "rust." It seems it is a solvent for aluminum oxide. Never had the opportunity to use this method myself... frames should be steel ;)

No, I'm referring to the left side, adjustable cup, the one with the lock ring. But thanks for the response. I read Sheldon Brown's link and it's no help because the adjustable cup is the newer, Shimano type design, a spanner won't work.
I don't know what you mean by a "newer, Shimano type design" but the nut and bolt trick should work on any cup of a loose-ball type bottom bracket.

Sheldon "No Spanner Neeeded" Brown

I don't know what you mean by a "newer, Shimano type design" but the nut and bolt trick should work on any cup of a loose-ball type bottom bracket.

Sheldon "No Spanner Neeeded" Brown
My error, I thought the thread had changed topics and stopped reading. Yeah, I think that nut and bolt tool should work. Thanks, I'll post again after I try it.

Sheldon Brown, thanks, that tool worked great. Removed the stuck cup with little effort. I used it again on another donor bike with a stuck cup. Worked great a second time.
Thanks Boss Moniker for providing the link.