The ornamental designs for a wishbone (heavy load) mounting arm, as shown and described.
FIG. 1 is a front perspective view of a wishbone (heavy load) mounting arm in accordance with an embodiment of the present design;
FIG. 2 is a rear perspective view of the wishbone (heavy load) mounting arm of FIG. 1;
FIG. 3 is a front elevational view of the wishbone (heavy load) mounting arm of FIG. 1;
FIG. 4 is a bottom view of the wishbone (heavy load) mounting arm of FIG. 1;
FIG. 5 is a rear elevational view of the wishbone (heavy load) mounting arm of FIG. 1;
FIG. 6 is a side elevational view of the wishbone (heavy load) mounting arm of FIG. 1; and,
FIG. 7 is a top view of the wishbone (heavy load) mounting arm of FIG. 1.
This design is not limited to the exact details shown in the figures, since equivalents and colorable imitations thereof will be evident to a person of ordinary skill in the art. Thus, within the scope of the appended claim, which is intended to cover only the ornamental and novel elements shown in the drawings, the invention may be practiced otherwise than as specifically shown and described herein.