Actually no...I just assumed they were but you are correct. They are plastic. It appears that whoever put the ugly aftermarket moulded ones on did a rotten job and broke all the tabs off or backed into something, or whatever. Anyway, all the tabs on the drivers side are broke off. Think I'll just have the pre-drilled ones sent back and order the ones you have to drill. There is still plenty of plastic left to mount to...just not the factory tabs. Poor design if you ask me.
I don't know if fiberglass would even stick to plastic if I tried to do a build-up and red rill the factory holes. I'm inclined to think not...not very well at least.
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