The structure of Ga overlayers on stepped Si(112) surfaces is investigated using the technique of Auger electron diffraction (AED). Although previous studies suggest that the Ga adatoms form well-ordered chains along the stepped Si(112) surface, no studies to date have determined the exact Ga adsorption sites on the Si(112) surface. However, low energy AED measurements on adsorbate structures are very sensitive to the adsorption site position and geometry due to strong backscattering from substrate atoms. In this work, low energy Ga AED data is analyzed using single scattering cluster (SSC) calculations. The analysis is able to differentiate between step edge and terrace adsorption site models for the Ga/Si(112) structure, as well as determine the detailed adsórbate geometry on the surface. The Ga overlayer model deduced from the data places the Ga adatoms 1.0 Å below the substitutions step edge sites of the non-primitive Si(112) surface.