I am putting a 136 kit on my 2002 XC and I have the tracks USA rail extensions on the skid. I am having trouble getting the metal rivets along the top out of the tunnel though!! I have used a very small bit to drill through them then come back with a bigger one but that is not working well and it is ruining all my bits!! Anyone have advice for me on this? Grinding them from the back is my next idea?