The ornamental design for a headlightfaceplatebase, as shown and described.
FIG. 1 is a perspective view of a headlight face plate base showing our design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom plan view thereof;
FIG. 6 is a left elevational view thereof; and,
FIG. 7 is a right elevational view thereof.
Dash-dash broken lines showing environment in the drawings are included for illustrative purposes only and form no part of the claimed design. Dash-dot-dash broken lines shown in the drawings define the boundaries of the claim and form no part thereof.