Do you have to clear the full $300 on Everest Poker?
Or do you get whatever you have cleared.. e.g. when you have cleared only $176 at the expiration date?
To get the money, you mean? It gets paid in 7c increments, so you get pretty much whatever you can clear. If you're unlucky you could miss out on like 6c at the end.
If you mean to get the books, that's not really related to the bonus $300, you just need to earn 50 summit points which means playing at tables where a total of $50 rake is taken.