5/16 (.311") valves. 10 deg Lunati retainers. 8MM 10 deg Lunati locks. A noted eng builder told me that these Lunati locks (dont have the part # handy) that are 8mm(=.315") are not right for my 5/16 (.311") valves. The Lunati tech (old guy with extensive exp) says that they are fine & with the "funnel" effect that the clamping will be fine. But then I went ahead & ordered a set of Manley 5/16 10 deg retainers (EDIT meant to say "locks") (13151-8) (2) pkgs of eight pairs & they have lash cap reliefs which I thought would take care of things (didnt see any WO lash cap reliefs which I hear lash caps are to be avoided anyhow) & the perimeter is slightly above the tip of the valve so they wont work. This (issue) is just starting to get to me. Can I (safely) stick back with the Lunati ones??? What do YOU guys think! & if I need another set, which ones? thank you for your time. EDIT Cuz I originally called Lunati as I had mistakenly thought my valves were 8MM & I thought my retainers & keepers needed changing out & he said neither needs changing.