I’m worried about the weight and stiffness of the cables too, and also managing what to do on the back of the Marantz with the small spring connections.
Pin to Spade or Pin to Banana. Leave the backend of that Marantz alone (original) unless you’re eager, willing, daring and have the technical know-how for such a mod. Reconfigure your rack to where the 2270 could / can be set close to the floor in order of cable support, or support cables with various technics. You’ll want to relieve sag! Trust me, I have a Marantz 2270 ....