Here are my spares, Challenger one on the left, Dart on the right..you can see they are similar. They actually use the same rubber cushion
I thing I have two left side Dart ones??
Should be an L or a R stamped into the nut retaining bracket welded into the guard. If it has been rusty you may not see this anymore.
The bottom is tapered to match the taper of the bumper.
Hope this helps all.
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