Just write it and stop stressing.
Treat it like any test and aim to minimize your weaknesses. Problems calculating NFP in time? Learn to skip those or drill yourself at those questions. Don't get family tax? Prepare a chart. Don't understand crim pro, reread the detailed table of contents then zoom into the sections you don't get. Rinse and repeat.
No point stressing about something you have no way of guessing.
Take away: You could get 90s in practice exams and still fail the real thing? I guess it's only good for keeping your speed on track, and getting you more familiar with your index.
Where have you seen these numbers?
I'm also writing in this cycle but I feel like that is a tough question considering nobody knows for sure what the passing grade is, and practice tests are apparently different than the real thing. There is speculation that you need a 70% to pass, but I have also seen other numbers like low 60s, or even 72.