Navigate over to the contract management section.
This will bring up a list of all the contracts divided by CSI Division. For example the first group of contracts might look like this:
A Prime contract can only be made a sub of sub if the prime contract doesn't already have a sub assigned to it.
Let's say Test Company 3 was supposed to be a sub to Test Company 1. Click the make sub link for Test Company 3. This will bring up a make a prime a sub of sub dialog. Select which contract Test Company 3 should be a sub to and click Mark as Sub.
When the page reloads Test Company 3 will now be a sub to Test Company 1.