I found , as Mr Mazza mentioned. That in my Fireball build the performance alloy push rods took quite a while to seat requiring frequent adjustment and producing a lot of aluminum flecks in the oil. When I took it apart I found the top pockets in the aluminum seem to have been too deep so that the rocker may not have actually been bottoming out initially so they had to carve their way down opening up the pocket as they went, I can't remember if I took pictures of what I found or not I will check or can do it next summer when I am home. So they may be simple to change but may open up other cans of worms....