Since you are ready for her to be trained, and at 4 she is more than old enough, go with your gut and proceed.
Your daughter knows this is one of the few things she can control in her life and she doesn't want to budge. So now you put the responsibility on her and back off. Tell her she won't be able to go to school (some will work with her but don't tell her that) if she isn't going to the potty on her own. Hype preschool up and tell her of all the things she will get to do there, IF she goes to the potty on her own.
As far as going naked or bottomless it won't help her not to pee, just make it easier for her to get to the potty without having an accident in her pants.
Don't give her rewards for not going, only when she's successful, and don't give her a reward she can hold, make it a "power incentive," something you retain ownership of and she gains 30 - 60 minutes of using it when she goes potty successfully. Take her out of pull-ups and go to cloth training pants so she feels the wetness next to her, impossible with pull-ups since they"wick" it away, and save the cute panties as a reward for being successfully trained for a couple of weeks.
Check out this site for lots of helpful information on potty training problems which deals with potty training refusers like your daughter. It helped me immensely to train my little guy when he was 27 months and ready, regardless of what his doctor or anyone said. I really didn't need to "push" him to train, just outsmart him : ) You'll find information on the "power incentive," putting the responsibility on the child, etc.
http://www.rogerknapp.com/medical/pottytrainingrefusals.htm