No--if facing the park entrance--the finish chutes will be to the left of the entrance in the parking lot (just past the kennel area). No ticket is required as the finish is outside the park.
For MK--they will let spectators in between 6:30am and 7:40am on Saturday for the half marathon and from 6:55am to 8:50am for the full marathon. No ticket is required and all guests without tickets will be escorted out before the park opens. However--all runners will be through the park by then and it is not a problem. It is mile marker 5.3 for the half and mile marker 10 for the full--so if you have a guestimate range of your split time--you will know when your family will need to be there.

If they make a poster--you can spot them easily as they will be screening thousands looking for you.