Chris,
Is revision A the revision that the CAD is being created at originally? And revision S or G is what you ultimately want?
Just looking for a little simpler/cleaner way to do things...there is a command line utility that you can use to change the revision letter of your objects. From a Windchill shell:
windchill wt.vc.ChangeRevisionLabelUtility -username wcadmin -password <password> -newRev <S or G or whatever> -oid wt.epm.EPMDocument:<id on the information page>
In this URL (the information page of the CAD document):
http://<Windchill>/servlet/TypeBasedIncludeServlet?oid=VR%3Awt.epm.EPMDocument%3A385899432&u8=1
the number 385899432 is the ID.
Therefore if I wanted that CAD document to be S instead of A, then I run this command:
windchill wt.vc.ChangeRevisionLabelUtility -username wcadmin -password <password> -newRev S -oid wt.epm.EPMDocument:385899432
Note that this effectively changes the A.1, A.2, and A.3, etc to S.1, S.2, and S.3. This may or may not be to your benefit.
See CS31039.
Does this seem useful in your case? The trouble will be getting the IDs of everything you want to revise. But if you want to go down that path, this forum can help you query those values also.