I have done it twice now. The 1st time, I tried using that tool at autozone and I guess my brain wasn't ready for it..hahahahaha...So I did it the hard way. I used a big breaker bar to hold the pully from moving and with a dull cold chisel I hit the nut. After about 10 hits, noting or I thought. Then this guy who is a master mech stop by and went to his house and brought back the biggest pair of adjustable grips I have ever seen. He put them on there and took my old cold chisel and said you just need to tap it. Well, unknown to me I had broken it loose and said Wow that was easy..hahahahahaha...Now the second time. I just used the old cold chisel and tap it a few times and it came loose, lucky that time. Didn't need to try and stop it from moving it came loose after a few taps. And who said they can't teach an old horse a new trick! Hopefully it won't happen again, I might not get so lucky...