First off, the easy part.
Here's a copy of the speakers owners manual. On page five, it shows that you would connect the RCA jacks on the back of the JBL transmitter to the RCA preamp ouit jacks for your surround channels.
Now,
here's the owners manual for your receiver and it's big brother, the 775.
Now, the hard part. Look carefully at pages 11 and 12 of that manual. While the 775, your receivers big brother, does indeed have the needed preamp out jacks needed to connect your wireless speakers, your 665 lacks that feature. You shoulda bought the 775.
Your only hope is to find something like
this that will allow you to convert your speaker outputs into a line level signal usable by the transmitter.
good luck.