[94SVTCobra|]

My car is a 94 SVT Cobra (#500 of 5009). Bought car 7 years ago with 55,xxx miles on it from original owner. I have put about 7,000 miles on car in 7 years. Tapping in upper portion of motor became increasingly apparent over time. I finally removed intake and rocker covers (i was the first person to remove the intake) and found about half of my valve retainers were worn and shiny due to bottom of the stock crane/ford RR's rubbing the top of the valve retainers during valve opening/compressing. One of the retainers was obviously being rubbed much harder than the others. I replaced that RR that was rubbing the worst and filed the bottom of the rest of the RR's so they would no longer rub. WTF is causing this? Has anyone else with a 94-95 Cobra been through this tapping/rubbing problem like I have? Motor is pretty quiet now, but i'm still F'ing pissed because like I said, I was the first person to go into this motor and now I need to replace most of the retainers. Ford is NO help and neither is SVT they both play stupid, probably because they really are. Crane is ****, don't buy crane, their QC sux.