just make up a bracket and screw it into the surround, then stick the AVCR onto that
I did the same thing with my blitz boost controller and power meter,
made the bracket out of some plastic/pvc(I actually cut and used a side of my old hi-fi system, was strong enough and had a nice colour to it ),cut, bent and shaped it to get the right spacing and screw position.
then some doublesided tabe to secure the 2 items onto it, looks perfect imo, noone knows its a backyard job
if u like i can take a pic to show how i did it, let me know