How to split out choral voices

Having imported a piece of 4 part choral music from a pdf, is there a clever way to split out a single voice, eg just the T from SATB? So if each part has its individual stave, how to remove the unwanted SAB staves completely? If combined SA and TB staves, how to remove the B, other than click and delete one note at a time?
(Similarly removing the T2 if it's 8 part)
Thanks