I had that worry for a moment, as I would barely touch the edge of the wheel well with the grinder and it would remove a good little bit. Then, I started getting to the solid metal and I could tell it. I did have to reshape the wheel well some to hopefully "get it right". My plan is to just "even up" the new lip I fabricate with the bit of original that's left and that should get me very close. It doesn't have to be perfect, just good enough to be able to clamp both lips together and then spot weld them together.