firewall pad fasteners?

[rideblue00]

What are you guys using for attaching the firewall pad? I bought these, but they are hard as stone. The first one I went to pound in...blew up in pcs. I suppose I may not know how to install these. The second one I used a punch down the center hole on it. But didnt use a hammer, just tried pushing it in by hand. Once I got to the bottom, the head popped off. They also stripped the paint out of the hole, im not happy about that either. Any help would be appreciated.