Make sure they understand the shift due to unbalanced, and make sure they understand that the wing is covered by a safety.
What I would do is leave the #3 QB blocking back uncovered, but I would have the OLBs key him instead of guards. Have the MLB play the 2 back, and the weak safety play the 1 back. This way you will take away their strongest plays. Then they'll be forced to run up the middle on you.