Installation is simple. Just loosen the 1" die retaining nut on the second or third die on your reloader. Slide the mirror arm under it and tighten it back down (picture below shows two 1" die nuts). You can tighten it as tight as needed. Remember to always check your depth settings on the die before reloading more ammo.
Once the mirror is in place, adjust it to the angle you need in order to see in the case from your desired position. You can bend the wire as needed (Do not bend the brass tubing). The mirror will rotate in almost any direction. If you ever need a longer arm, there is some extra length in the brass tube, simply pull it out. If you find it's not long enough, simply contact me and I will rush a longer one to you.