Abstract: Apparatus for gauging the alignment of a multiplicity of bearing seats lying along a common reference axis comprising an elongated shaft, first and second bearings for rotatably journaling the shaft in a pair of reference bearing seats, a radial distance indicator mechanism coupled to a collar slidably mounted on the shaft, and a means to contact the radial distance indicator mechanism to selected bearing seats. When the shaft is rotated with the radial distance indicator mechanism in contact with the bearing seat, eccentricity of a selected bearing seat can be determined with respect to the reference axis.