The ornamental design for a portion of a vehicleexterior, as shown and described.
FIG. 1 is a perspective view of a portion of a vehicle exterior showing my new design;
FIG. 2 is a side elevational view of one side, the opposite side elevational view being a mirror image thereof;
FIG. 3 is a front elevational view thereof; and,
FIG. 4 is a top plan view thereof.
The broken line showings of the trapezoidal shape on the hood, curved area on the side panel, the headlight areas, and the cross-piece in the intake area are for illustrative purposes only and form no part of the claimed design.