You should first call Disney and ask then to add a room request if you haven't where you can ask for your buildiing and ground floor, with note of
ECV so they understand your need for accessibility. On TP, after you choose those options, there should be a map on the right, with rooms highlighted that match your choices. Then if you click on a highlighted room in the building you wanted, you can see a view from that room, and when you see one that matches with your requests, you can click on "request this room.". Then it will show up on your dashboard, along with other info. if you gave plugged in dates and reservation number. They send the fax about 5 days out since that is when room assignments are supposed to be made, so you want to do it now so you get requests made ahead of that. Remember they are only requests, so if when you arrive they have given you something else, you can politely remind them of the request you called in that is on your reservation, and ask if they could accommodate you. They will usually try to help if there is availability.