" perspective view of a portion of the scraper assembly in FIG. 7;FIG. 9 is a partial sectional elevated side view along the lines IX--IX in FIG. 6;FIG. 9a is the same as FIG. 9 except that the adjustment screws have been rotated to pivot the supporting surface of the mounting bracket assembly;FIG. 10 is a bottom front perspective view of the scraper assembly of FIG. 2; andFIG. 11 is an exploded vi" . . . .