I put a tiny nick in mine... I little sliver on the leading edge and I haven't noticed any issues.Just finishing this up. Wasnt to bad except it took about 10 attempts to get the ball bearings back in. Only thing I am questioning is I shaved a sliver of the teflon ring putting the power piston back in. Question is, has any one else shaved the ring a bit and did it have any negative impact? The oem ring looks fine so I could pull the piston and re install it. Also tapped the box for hydro assist.