Title basically says it all, I'm having some trouble understanding how to remove the platen. I was able to remove the right platen knob with the typical screws (although they were hard to get at). After that, there's an easily removable piece of metal that lets you lift the right side of the platen out. 

My problem is the left side, I really don't see how it's supposed to come out, does anyone know?

Thank you for your time and your help!