Found the difference between the 2008 Main Post and the 2010 Main Post. All measurements, lenghts and angles of the main tube and ski-to-post attachments are the same. The change is on the bottommost flange.
On the 2008, the bottommost flange is flat, but has two little ears on it so its not just a simple flat sided, round flange. The 2010 bottom flange is a flat, round flange.
Nothing the grinder won't be able to fix.