Per Pa DOR customer help website answer to question on it "I efiled & have documents to attach. How do I get attachments to the department?" :          1.) document can be faxed directly to PA DOR  2.) PDF file  can be directly emailed to pa dor. or 3.) can be mailed directly to it.   You may want to consider asking client if he just wants to mail the entire return and supplemental documentation - client can opt out of efiling directly on PA40.