How many cables are required between the dish and the following receivers, 1 SD & 1 HD? Does it matter if the distance is over 120'? Would dual RG6 normally be run from the dish in this kind of install (the cable has to be buried) to facilitate any future upgrade to a HD DVR? I'm upgrading all my inside wiring to RG6 to get my house ready to accept a D* install and I want to be sure I have all the bases covered. TIA for your help.