OK, so first if there is any evidence of rust on the threads, lay it on the drive side and apply your favorite rust solvent and let it sit for a day or so to let it work. Next, hold the pin spanner over the cup with the palm of your left hand, and give the end of the spanner a series of quick sharp impacts with a plastic mallet or other wide faced object. This should break the bond between the cup and BB threads. If this does not work, we can discuss other ways to remove the cup that will damage it but not harm the frame.