Is it, the fastener you need to remove, male or female? Will the removal tool be inserted into the fastner, or will it go over/around the fastener? There are both normal (female) Torx, and reverse (male) Torx fasteners, and it's not uncommon to see either used for pulleys. Do you have the ability to post a pic? That could go a long way in getting a good answer. Let me know and I'll be able to tell you which you have, and then hopefully, what you need.

MV