I claim the ornamental design for an tightening side plate for textile machine, as shown and described.
FIG. 1 is a front perspective view of a tightening side plate for textile machine according to the present design; the phantom lines shown in FIGS. 1-8 indicating features which form no part of the claimed design;
FIG. 2 is a back perspective view of the tightening side plate for textile machine;
FIG. 3 is a front elevation of the tightening side plate for textile machine;
FIG. 4 is a back elevation of the tightening side plate for textile machine;
FIG. 5 is a top view of the tightening side plate for textile machine;
FIG. 6 is a right side view of the tightening side plate for textile machine;
FIG. 7 is a left side view of the tightening side plate for textile machine; and,
FIG. 8 is a bottom view of the tightening side plate for textile machine.