I can predict what will happen on the border if Mr. Trump wins and that victory is obvious by a day or two after the election:
Watch for all border crossing points to have their gates and barriers locked open, and for border and customs officers to be ordered to "stand back and do nothing" as the hordes flood the gates and sweep in unrestricted.
This will continue from about November 7th until January 21st.
Then we'll see how serious Mr. Trump is about getting the border under control...