Andrew, thanks for this question. Since you have been a member for a while and have made over 50 contributions, you can be pre-1700 certified.
It appears that you would just need to sign the Honor Code if you haven't already. Then, take the self-certification quiz.
You can find the information for this if you go to the Help tab on the upper right of your profile page. In the drop-down box scroll down to Certification and you will see pre-1700.
I hope this helps and good luck on the quiz!!