At 0.790 gross lift you should be using high quality rocker arms, especially if you're going to turn the engine past 6000 rpm. T&D is probably the best choice at that level although a switch to Jesel could also make sense if the engine is designed to make a lot of passes. I would not run anything that deflects as much as what you are measuring. That deflection will occur every rotation of the engine so those shafts will be vibrating like guitar springs at 6000 rpm.