Hello, i could use some help with this one. I am replacing the front sway bar bushings on my 1990 convertible and when I went to unbolt the sway bar from the bottom, there was this plastic clip on the top side that held (and presumably) prevented the screw from spinning as I tried to spin the lower nut. As you can see from the picture, it was plastic, and after 25 years just disintegrated. I've looked online and in some Chilton's manuals and cant seem to locate this part. Do I even need it? If so, any idea where to get it?

Thanks for your help.