Can't remove subplatter


I can't seem to remove the subplatter from my Rega P3 turntable.
when I pull it seems to be firmly attached to the mechanism.
should I pull harder or is there some trick?
i don't want to break it.
128x128rvpiano
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Viridian, Thanks for your response.
 It worked! I got it off.
I didn't realize how it was attached. My pulling wasn't going to break
anything.

 I'm replacing it with an aluminum platter.  The consensus is that this 
replacement is one of the best tweaks you can make to a Rega turntable.
i just ordered the new subplatter and wanted to see how to remove the old one.

Again, thank you.

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