You can score quite high in Saunders I was getting over 90% most of the time & I passed with 75. You probably know your content well so now you need to check your critical thinking skills.
Try the Mosby on-line CAT test. It will give you your probability of passing N-CLEX & so far, judging by those who have used it on this site (including me), it's been correct.
If you have time try & do at least the 1 day live Kaplan course - or the 5 day if you can. The questions on Kaplan were just like the one's I had in my exam. This would really help you hone your critical thinking skills.
Failing that you could sign up for the NCSBN on-line course ($49 for 3 weeks.) Just go straight to the questions each time - only look back at content if you get too many wrong. I had at least 2 questions in my actual exam that were on that site.
Then good luck, relax, you know you can do it!