I presently have a Eagle DTVP3, 18" x 20" dish supporting three standard (non-HD) receivers. All receivers are wired directly to the dish. I would like to swap out one of the receivers for a standard (non recording) HD Receiver. I'm told I will need to install a new dish in order to receive HD channels. Can someone recommend the proper dish to replace the one I presently have? To keep things simple, all I want to do is remove the existing dish from its pole and replace it with a new dish and reconnect the three wires for the receivers. I'm not interested in a single wire system. Thanks in advance.