sure. fcp will automatically adjust this when you edit a clip into the sequence, so after changes the sequence settings, simply edit a source clip at the end of the sequence. Does it display correctly? If so, select the clip, copy, and then select all the other clips in the sequence, hit option-v (paste attributes) and make sure just basic motion and distort are checked. Should fix everything. Then delete that clip you added at the end of the sequence.
Oh yeah, probably a good idea to duplicate your sequence before doing this, in case you make a mistake (or if I've made a mistake - nah, that wouldn't happen).
Thanks Mike. Will try this today. so I will see the cinemascope anamorphic 2.35:1 ratio? and no distortion?...I saw one method where you simply use the Widescreen on Matte under video filters...select 2.35:1 and crops off 130 pixels from top and bottom. And then with quicktime 7 you can remove the black bars on top and bottom to create a true 2.35:1 cinemacope anamorphic widescreen video.