The ornamental design for a snowmobile side panel, as shown and described.
FIG. 1 is a perspective view taken from a front, right side of a snowmobile side panel according to an embodiment of our design;
FIG. 2 is a perspective view taken from a rear, right side thereof;
FIG. 3 is a right side elevation view thereof;
FIG. 4 is a front elevation view thereof;
FIG. 5 is a left side elevation view thereof;
FIG. 6 is a rear elevation view thereof;
FIG. 7 is a top plan view thereof;
FIG. 8 is a bottom plan view thereof; and,
FIG. 9 is a perspective view taken from a front, right side thereof shown on a snowmobile shown in dashed lines.
Throughout the Figures, where shown: (i) the dashed lines showing additional structure of the snowmobile side panel are for illustrative purposes only and form no part of the claimed design; and (ii) the unshaded surfaces bound by dash-dot lines form no part of the claimed design. A second embodiment of the invention includes the minor image of the embodiment of the snowmobile side panel shown in the Figures.