I think Perk will avoid the 7th T, he has gathered himself very well in the Finals, kudos to him (although I saw on the replays of game 4 that he went nuts on the bench during the 4th when Kobe got some calls

).
Sheed, however, is more of a concern, he just can't control himself and he went crazy last night... hopefully he does a better job of controling his emotions in game 5 and beyond.