I claim the ornamental design for a portion of a truck cowl hood, as shown and described.
FIG. 1 is a front elevational view of a portion of a truck cowl hood
showing my new design; the broken lines are shown for illustrative
purposes only and form no part of the claimed design;
FIG. 2 is a front and left side perspective view thereof; and,
FIG. 3 is a left side elevational view thereof, the right side being a
mirror image of that shown.