The University of Michigan's Museum of Anthropology has digitized their cranial collection, which consists of (I think) around 160 skeletons. I couldn't find much information about the Ford Collection of skulls, but I assume they are not Native American and are possibly more long the lines of the Morton Collection at Penn or the Terry Collection at the Smithsonian, based on this report:
[The] collection [was] created by Corydon La Ford, MD (tenure 1854-1894), University of Michigan, Medical School, Department of Anatomy. The collection was created by Dr. La Ford during the late 19th century and it was later added to by unknown individuals until the early 20th century. The collection was used for anatomy teaching in the Medical School and no information exists as to how the crania were acquired.