The ornamental design for a portion of a shoe upper, as shown and described.
FIG. 1 is a perspective view of a portion of a shoe upper showing my new design;
FIG. 2 is a side view thereof;
FIG. 3 is a front view thereof; and,
FIG. 4 is a top view thereof.
The even broken lines in the shaded area represent stitching. The uneven broken line immediately adjacent to the shaded area represents an unclaimed boundary of the design. The uneven broken line showing of rectangular and circular regions in the shaded area form no part of the claimed design. The uneven broken line showing of the remainder of the shoe is for illustrative purposes only and forms no part of the claimed design.