Recently a Chinese stegosaur was found with both spikes of the same type clearly placed on the shoulders (originally thought to be a Tuojiangosaurus specimen, turned out to be Gigantspinosaurus). So that type of spike is always placed on the shoulder in view of the lack of evidence for the pelvis.
Yes, except that that -- _still_ unpublished -- specimen has a very broad base to its shoulder spines that runs in parallel to the scapula. No such thing exists in *Kentrosaurus*.
Photos have been published. I just forgot where. Maybe in Glut's Encyclopedia?