you failed maintanence 101, proper service and lubrication..it would not be frozen. spray the hell out of it with pb blaster a couple times thought the aftrnoon/evening and again in the morning before you take off for school. the after it has had 24 hors or so, loosen the nut so that its face is flush with the end of the pivot bolt. grab a BFE and get busy. there really is no practicle way of getting a hot wrench in there so you have no choice but to resort to inertial amplification.