[masraum]

Originally Posted by DWBOX2000

I started drilling the bolts out and they just popped through into the wheel well. Looks like there is nothing to screw into but they were somehow anchored somehow from the back. Just holes in sheet metal to attach. I was thinking nut and bolt but really don’t want to take plastic wheel well liner off. I just know it will cause other issues. Any suggestions on attaching the lid? Thanks

My guess based on your description and issues is that they were riveted on. That's why you couldn't get anything to "bite" in the "bolts" because they weren't bolts so their was nothing to bite.

You could try to find a pop rivet gun and rivets that are big enough, but how big are those holes? They look pretty big.
You could try to get to the back of the area through the wheel well and then use bolts and lock-nuts. You could also use short sheet metal screws.