ok, well you can simply use 2 diseqc switches.
all 3 into one of them from one port out each.
and do the same for the other.
then out from the switch to one receiver and out from other switch to other receiver.
however there are some common problems when doing this,but can be easily resolved here:
http://www.abadss.com/forum/29-lnb-d...receivers.html