The ornamental design for a pair of dipperdoorstructure plates, as shown and described.
FIG. 1 is a perspective front view of a pair of dipper door structure plates, a portion of the structure plates being broken away to indicate indeterminate length;
FIG. 2 is a front elevation view of the pair of dipper door structure plates;
FIG. 3 is a rear elevation view of the pair of dipper door structure plates;
FIG. 4 is a left side elevation view of the pair of dipper door structure plates, the right side view being a mirror image thereof, a portion of the structure plates being broken away to indicate indeterminate length;
FIG. 5 is a top plan view of the pair of dipper door structure plates, a portion of the structure plates being broken away to indicate indeterminate length; and,
FIG. 6 is a bottom plan view of the pair of dipper door structure plates, a portion of the structure plates being broken away to indicate indeterminate length.
The dipper door is shown in broken lines for illustrative purposes only and forms no part of the claimed design.