How to disable PB Tools Password

I found my original Powerbook 170 in the attic and it still works ... boots up with a happy Mac BUT I have put PB Tools on it and cannot for the life of me remember my password. I found an old discussion about PB Tools that said to press the shift bar on rebooting, but that does not seem to be working, unless I've forgotten something about rebooting my 170.

What I'm doing is holding down the shift button and then depressing the on switch. But, nothing happens until I stop pressing the shift button. Then the computer turns on, goes through start up and then asks for the darn password again. What am I doing wrong? I think coming up with a 20+ year old password is unlikely. Already tried everything I can think of that I would have been using back then.