Dean,

On my 9A tipup, the EC2 is located on the back side of the subpanel directly in front of the pilot. 4 #8 screws go in from the aft side to nutplates inside the box which is easily accessible from the cockpit. The plug with all those wires which hopefully Tracy understands what they do :>) is aimed toward the firewall where many exit thru a stainless elbow cut from a handicapped grab bar. This location has been very accessible to check wiring (ask my how I know :>( ) of the EC2.  My EM2 box is mounted on the outboard side of the port deck rib. It also has many many wires running firewall forward to the sensors thru the same access tube. This set up has worked very good for me. One of the things at this point that I would not do different if starting over.