A/V Receiver Sits Behind Plasma TV. Problem?

Here is the deal. I installed my 7.1 surround sound yesterday. This was the Onkyo HT-S5500(B). Due to the layout of everything, the Receiver must be placed in an alcove behind the Panasonic plasma TV. This is completely screwing up my ability to control the receiver with the remote. What is the cheapest option to be able to control the receiver while it sits behind the TV. Moving the receiver is not an option. I'm not sure if a Harmony remote would help in this situation. I own one from 4 years ago, but it is used in my daughter's bedroom. After spending so much money to get this thing to my house and then installed, I just want this problem to go away. Any suggestions?