I think part of the reason Kalis made the switch is the bond he already had with Tom Strobel and Chris Wormley. He is good friends with Strobel and he has a lot of respect for Wormley's game.
And I don't think the UM staff likes him at guard, I think that is just where he may potentially wind up.
Michigan commits Erik Magnuson (6'6, 275 lbs., #34 player in nation according to Rivals), Blake Bars (6'5, 270, 4* on Rivals), and Ben Braden (6'7, 315, run of the mill MI 3*) are all scouted by the major services as OT's, and Michigan is still very much in it with Jordan Diamond and Zach Banner (who are both stricly OT's, and who are both taking OV's to Ann Arbor) and possibly on the outside looking in at Andrus Peat (cut his list to a top 8, MI is in that group and he took an unofficial to Ann Arbor about a month back and may take an OV in the fall) and Josh Garnett (who has scheduled an OV for the Nebraska game).
I'd say Diamond is most likely for UM from that group of 4, Banner next, and then the other 2 are more or less longish type shots.