Ok, so now that I’ve done a few interviews, and I’m starting to get a sense of maybe where I am gonna rank 1, 2, and 3. What can I do to increase my chances of getting my 1st choice? I have never really gotten a solid answer on this. Do I email the program director and let him know that I really want to go there, or do I even go so far as to tell him/ her that they are my first choice? And what about thank you letters? Do I tell them in those things? I've also heard that thank you letters sometimes go in your file. Is that true?

The main question I have here is what can I do now, post-interview, to get my top choice.

Thanks in advance!

I was wondering the same. My top choices seem to be fairly competitive places. While I intend on sending thank you cards and impressing how much I'd want to go there, I don't know what else to do... maybe drop a hint during the interview?