The ornamental design for a cheekrestassembly, as shown and described.
FIG. 1 is a perspective view of a cheek rest assembly showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a bottom plan view thereof;
FIG. 7 is a top plan view thereof;
FIG. 8 is a right side perspective view thereof;
FIG. 9 is a perspective view showing the cheek rest attached to a firearm stock; and,
FIG. 10 is an exploded perspective view of the cheek rest assembly.
The broken line showing of straps, slot drives for fasteners, and firearm stock is included for the purpose of illustrating environmental structure and forms no part of the claimed design.