REL S/3 (2) subwoofer connection question

I am attempting to connect two REL S/3 subwoofers to a Rogue Audio Cronus Magnum II integrated amp. I am using the REL Neutrik Speakon cables. My understanding is that one sub connects to the left channel speaker binding posts and the other sub in the right channel speaker binding posts.
My question: Do I twist the yellow and red Neutrik speaker wires together and put on the positive (red) terminal and the black wire on the black (ground) terminal for each channel?
I am using spade connectors for my speakers. Do I place the spades against the speaker binding plate on the amp connection with the Neutrik wires on top, or the Neutrik wires under the spade against the plate?