I think TA's spot is safe unless he plays terribly, not only will they need him defending Lebron, but he will be needed to defend Delonte and even Mo Williams at times. While Quis has 3 inches on TA, i believe there is only about a 1 inch difference in wingspan. Tony is probably stronger and definately has quicker feet on defense which is more important than height against Lebron because you gotta keep him infront of you.
I think its more liklely Finley is the odd man out this series, he is the last wing we wanna see on Lebron, and didnt really do anything against the Heat. I think Tony will get around the 16 mpg he got in the Heat series because ontop of defending Lebron for stretches, he is going to be the backup pg. Then i expect Quis/Finley to share the rest of the minutes, depending on the matchups and if we need help on offense or defense.