Here are the parts. The connector arms are actually two parts glued together. I did not think of showing the parts seperated.
And here it is on the battlewagon. Be sure to dry fit the parts together so you can still the battlewagon down without the deffrolla being too far down. You do not need to glue the actual rolla part to the arms. It adds some length to the model. When you glue it to the battlewagon do it one side at a time and use the rolla part so the arm sits where you want it and it will also hold the arm in place while it dries.