I found this:
So far we have five verified connection schemes to combine multiple dishes at different locations to receive signals from all DirecTV satellites through trees and other obstructions ....
1. Use two AT9 dishes, one sited to receive 99/101/103-deg W and the other sited to receive 110/119-deg W and described in more detail earlier in this thread:
2. Use one AT9 dish without the "sidecar" LNB sited to receive 99/101/103-deg W and two 18" round dishes to receive 110 and 119-deg W, with the 110-deg W dish using the special "Sat C Kit" LNB and combiner:
3. Use one AT9 dish without the "sidecar" LNB sited to receive 99/101/103-deg W and one Phase III multisatellite dish to receive 110 and 119-deg W:
4. Modify a SlimLine LNB assembly to disconnect the 110 & 119-deg LNBs, then combine with two round dishes or a Phase III dish as described in 2 and 3 above. See Carl's post with modification instructions and photos here ....