I just found the manual for Installation and Maintenance of the Spot Tuner C 131/AR. This manual ( AN 08-35C131-2 ) shows the installation of the tuner on ARA / ARC-5 Receiver with wiring diagram and how to operate / set it. I will try to scan it into my computer, so it can be downloaded. It is 32 pages . If interested please let me know. Peter KC0DGM