A kit for use in joint arthroplasty that includes a first component of a prosthesis, a second component of the prosthesis, and an assembly tool for assembling the first component to the second component. The tool includes a housing for contact with the first component and an internal component connected to the second component. The internal component includes an actuating device and an actuator rod. The actuating device has at least one scissor arm. The housing and the internal component are adapted to provide for the assembly of the first component of the prosthesis to the second component of the prosthesis. The internal component is adapted to provide relative motion of the internal component with respect to the housing when the at least one scissor arm is moved relative to the housing, the relative motion of the internal component with respect to the housing being utilized to effect the relative motion of the first component with respect to the second component to urge the second component into engagement with the first component.