Letter to her. Someone please answer im desperate

I typed my girlfriend a letter. We’re having a rough time right now. Im going to give her her the letter regardless of anything. I just need one thing from everyone. Here it is:

I want to put at the end of the letter, that she will meet me somewhere after she reads it, if she chooses to stay with me after she reads it. The problem is her family. She is mexican. Her parents are very strict. Sh has 3 other sisters living at home. With a brother in law, a niece an nephew. And of course her mother and father. She just got a car since she got her license. So she would be able to drive to where I will be waiting. Butim just scared that she just wont be able to you know. But then again I want to test her love for me to see if she would do it. And by the way we have been together for a year and a half and we have told everyone about us. Her whole family knows. We just havent told her father. So this will be life changing. So please leave me your opinions. Should I tell her to meet me at the beach at a certain time after she reads the letter after I get out of work ( which is when I will give it to her) or forget that and just let her call me instead? Remember if she rebels, and does this. It could be life changing, beceuase of her disobidience. She doesnt disobey he parents. But should I do this or not and please answer immeidetly (dont know how to spell that sorry)

Thank you