SME 3009 II (improved) won't balance with Shure V15 III

So ... I'm working on a Garrard 301 project and just installed a new-to-me SME 3009 II (improved) tonearm on which I attached a Shure V15 cartridge. I know that this cart and arm are essentially made for each other, but when I begin the setup process, I can't get past the first, most basic step. Even with the balance weight screwed in as close as possible (applying no extra upward weight), the cartridge end tips way UP when I release it from the arm rest. No adjustment I make will get the arm to come down into a balanced position.

I've never encountered this with a tonearm before, and I'm new to owning an SME. 

I'm pretty sure I've check all the "D'oh! How could I be so stupid?" things I could be doing wrong. I'm baffled.  Anyone have any ideas? 

Thanks in advance!