[rhandwor]

The only left hand threads i have found on autos were lug nuts and they had a L stamped in the stud.
I am suprised it didn't break if it is this tight. Use a 1/2 breaker bar and a impact socket. Bump it a strong pull will break it. Try a 3/8 impact wrench.
Are you on the bolt some studs are welded on for loosening the belt as they are welded they don't turn. I really think this is the case.