You may want to read this thread
First,
There are dual RG-6 cables called "Siamese" which are easily found at online dealers who sell cables. This may simplify your cable pulling. This is a dual RG-6 cable which can be split into two seperate cables at the appropriate location.
Second you may want to peruse this thread about splitting LNB signals.
Hope this helps:
http://64.21.8.90/forum/showthread.php?s=&threadid=8122
madd0c
Yes, there are two paths you can go by, but in the long run, there's still time to change the road your on.
Led Zeppelin