I bought one of the original 62mm sets and reading about the problems on here took apart an old TPS to see what was going on. The stock shaft is extends all the way into the female split plastic "D" bush and is pinched at the top by a round wire snap ring. For some reason the 62mm shaft is short and does not extend up to the snap ring. This results in the shaft not being gripped properly and allows a small amount of play. I fixed the issue with a small "L" shaped shim which applies a slight amount of pressure to the bush and removes the play.
I fixed the problem with the shaft - 
