Improved sealing at the pushrod tube gland nut

My friend Jack Hogan, when visiting from Australia showed me how to convert the two piece pushrod tube to be far better, and using an o-ring. instead of the packing string. The really clever thing that Jack showed me, and not done by anyone else that I am aware of, is to make a small ring to go against the o-ring - as o-rings do not like sliding - only direct compression, and can often jam the big center gland nut. By dropping a compressing ring in first into the recess opened up for the o-ring , then the o-ring, on assembly, the o-ring is back to only compression -the gland nut slides on the compressing ring, and not directly on the o-ring. The o-ring is now back to compression only - what it was designed for. - This method he said is used in commercial applications like steam piping, etc