The ornamental design for a tractor cowling with side panels, as shown and described.
FIG. 1 is a front elevational view of the tractor cowling with side panels
showing our new design, the broken lines showing an exhaust pipe
projecting through the top of the cowling are for illustrative purposes
only and form no part of the claimed design;
FIG. 2 is a reduced top plan view thereof;
FIG. 3 is a reduced right side elevational view thereof; and,
FIG. 4 is a reduced left side elevational view thereof.