The measurements were the hinge that directly attached to the machine.
I didn't know about the ISMACS site. Will have to check that one out. Just joined NeedleBar last week but haven't had a chance to check that one out.
There is another site where you can ask questions and they are ususally quite quick in responding. That site
http://groups.yahoo.com/group/vintagesingers/
There is a lot of info in their files, but as I said they are quick in responding. You do have to join though.