Got it. The link in my original post has a detailed 2er installation walk-through. Another member struggled with the connector keying, I think maybe they forgot to swap the housings. The guide covers all this. I used a spare hole in the main amp's mounts as a mount-point for the original cables tie-down then cable tied the new harness to the mount-point I removed the original cable from on the ASD module. It was easy to do a clean install.
There's almost zero sound deadening in the trunk...made me wish I had a roll of dynamat on hand. There was a big slather of glue on the driver's wheel well in my car; someone must have been preparing to do an M235i sound dampening install when they realized it was an M2.
