Well, it doesn't really matter as he did such a great job. He's not the only one who hated his role in a particular movie. Sean Connery hated acting as James Bond, yet he's considered one of the best JB actors.
But yeah, this is about Sir Alec.
BTW, if he hated SW, how did GL manage to persuade him to return for ESB and RotJ?
Duct Tape is ALWAYS the answer