Connecting to single REL T7

Hi

Anyone out there have a 14B-squared and single REL T7 (or other) sub-woofer? I want to figure out how to connect my one T7 to the speaker out terms of the 14B-squared.

The REL manual's diagram is attached. Note bottom diagram, for fully diff bal amps. The 14B has no ground screw on the chassis, which is specified in the instructions for connecting one T7 to a fully diff balanced amp.

So, where would I connect the black REL wire? (I've contacted REL, awaiting there response there). Note: I use only SE inputs, not bal on the 14B.

Thanks for any help.
Pete

Methinks this should work. I shall loosen one of the corner screws on back panel, just enough to wrap the tip of the REL ground wire around it. That's what REL recommends for diff bal amps. Any objections?