Nut Slot files which to buy? - Repairs and Technical

Uo-Chikyu Nut Files by Hiroshima Files guitar nut slot files I'm really getting them to lower some nut slots in my current guitars, not make new nuts, but it may come to that if I stuff it up! guitar nut slot depth Hosco Hosco Compact Black Acoustic Guitar Nut File Set w Aluminum Holder MSRP: Now: $ Was: Hosco Compact Black Bass Guitar Nut File Set w Aluminum

guitar nut slot files 008 gauge string would you use a file etc, that kind of thing? Ultimately I want to get the nut slots spot on and I have guitars which I use sets of 8-38,