It caps an impressive start for all three promoted clubs - with runners-up Bristol City currently topping the table and Scunthorpe collecting seven points from their opening five games.
"I think the fact that we are sixth is a fair reflection of what we've done and how we have started, but we are not getting carried away," said Grayson.
"We know that we've got a lot of hard work in front of us, but at the same time it is a reflection on how we've played in the games so far.
"We won't get carried away by the fact that we're sixth. We've got to keep doing the same things on a daily basis.
"Where it will take us come the end of the season we will have to wait and see, but there are certainly lots of positives so far."