I have eaten there twice with large groups.
The first time there were 12 of us. One group of 6 sat in a car and the other 6 were in one of the table cars behind the other group. Not ideal but we'd been waiting for about 30 minutes, this was the last day of our trip and everyone just wanted to sit down and eat. I believe that reservation was for around 6:30 on a Sunday evening.
The next time there were 8 of us. They seated us in cars next to each other (4 in each car) and it was great. That reservation was in the middle of the afternoon, around 3:30 or 4:00, on a Thursday afternoon so the restaurant wasn't as busy as the previous time.
We love the atmosphere at this restaurant. Have a great time!