We use separate files as kohanmike mentioned, e.g.:
Amazing Grace - Chains - SATB (F).pdf
Amazing Grace - Chains - Violin 1 (F).pdf
Amazing Grace - Chains.cho
Amazing Grace - Chains - Piano (F).pdf
Amazing Grace - Chains - SATB (F).pdf
Amazing Grace - Chains - Violin 1 (F).pdf
Amazing Grace - Chains.cho
Amazing Grace - Chains - Piano (F).pdf