Here is a thread and pic of my setup
http://www.satelliteguys.us/2006035-post14.html

The azbox can see C-Band (99W), 105 KU and a feed off either motorized. So today I was flipping between a game on 99W (ABC HD), a game on 105W, a game on 91W via the 2nd motorized while I was still scanning using the main motorized

another option and I guess it would work is to put a diseqc switch on the loop out of both receivers to the azbox

merc ii loop out-----diseqc 1-----------azbox
dynamic loop out----diseqc 2

then power off the receiver that you want (C or KU) which gives you both polarities....otherwise you only get the same polarity as what the "main" receiver is set to

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Winegard 76cm dish, SG2100 motor, Sadoun dual KU LNB/DirecTv dual..... Fortec 6 foot dish with GeoSatPro dual C-Band LNB aimed at 99W... Primestar 84e aimed at 91W.... WSIDigital 4 foot dish with Sadoun dual LNB aimed at 105W with 2nd LNB for 101W.... GeoSatPro 36" dish, SG2100 motor, Sadoun dual LNB
Coolsat 5000 on motorized....AZBox HD Elite on 99,motorized,105....Viacast DSR1500 on 99....GeoSatPro DSR200c on 2nd motorized.... Directv D15 DVR on 101W.... Pansat 1500 to aim dishes.... few receivers not set up yet
Other 6 foot Fortec dish with GeoSatPro dual C-Band LNB "ghetto moved" to various C-Band satellites
Third 6 foot Sadoun dish with GeoSatPro Prime Focus KU LNB on it for maximum rain fade combatting