I'm in a similar situation. I thanked the GDS for being so forthcoming with my particular position, and in return assured her that the school was on the top of my list. If this school is indeed your top choice (or one of them), I think that's worth mentioning, but that's all I would share. He knows everything he needs to about you, and he's a busy guy. If the school is nearby, there seems no harm in checking things out in person, but do that for yourself.