Methods and devices for preparing an acetabulum for receiving an acetabular component in a hip replacement procedure. The methods may include aligning a first guide in an acetabular notch of the acetabulum and determining a reference point in the acetabulum. The first guide is removed from the acetabulum and then a second guide is positioned in the acetabulum and oriented with the reference point. While the second guide is positioned in the acetabulum, the acetabular margin is reamed with a reamer. During reaming, the reamer is contacted against a rim of the second guide which prevents additional reaming of the acetabular notch below the rim of the second guide.