Disclosed apparatus and methods confirm the depth of insertion of an acetabular component in the course of a total Mp replacement using a graduated shaft through a cannulated holder. Embodiments are disclosed including a version integrated into existing instrumentation, and an alternative, disposable version, one per case. All of embodiments confirm appropriate seating of the acetabular component against the inner wall of the acetabulum. Given the hemispherical reaming that is done during acetabular preparation, this would allow for maximal contact between the prosthesis and the host bone.