A trial system for determining a suitable proximal body implant for hip replacement surgery comprises a separator instrument, a trial body attachable to a distal stem, and an insert. The insert is positioned within the trial body to receive the separator instrument. As the separator instrument is rotated about its axis, a ramp element of the insert guides a pin of the separator instrument, so as to separate the trial body from the distal stem. Additional apparatus, methods, and systems are disclosed.