Here is video of Williams at the plate and you can see his wheels to first.
Btw, Mason Williams is an example of what was referred to on draft night on MLB network as a scouts draft pick. That is, a guy you have to have experience "projecting his skills into the future" once he is fully developed physically. Tough thing to do, but the best scouts peer into a crystal ball to see what a kid like Williams can become. I think the Yankees minor league player development people are going to have fun working with this kid.