How to hide lowest level of unit set on ARM report.

I have a case where I had to create a a level in my unit set because I hit the character limitation for subaccount in the data source. When the user runs the ARM report I want them to just see the top level of all and the 2nd level of CONTRACT, COOP AND COOWNED. How can I hide the lowest level? I have attached a screen shot of my unit set for a visual. I am grouping data by subaccount to the three different types of Contract, COOP and Co Owned. There is not range or account class that I can use so I had to go this route to get past the character limitation.

Sara