I changed my valve springs today and in the process I took apart the valves to clean up the assembly and of course I broke two of the little nylon buttons that keep the rockers from sliding from side to side. I've called every GM dealer in my area and no one knows what I am talking about. Three tried to get me to buy the compete rocker assembly. What can I use as a replacement for these? Or if anyone knows a specifc part number for these nylon buttons, I would be more than grateful! Anyone have some spares laying around they don't need? I'd be more than happy to send some money for them. Thanks guys!