This is the issue we have as well, but it's not really a proper work around. Copy 2 will not let you suppress the printing of the ss# and since they don't line up right we'd just be mailing forms with everyone's SS#, full name, and address on display for everyone to see.  Obviously that's not the answer.  All in all its just a complete mess this year trying to print these things and get them into the envelopes that we were told to use.