From what I have read the 105 superdish can be modified to receive the 118.7 satellite. The 121 is not able to work.
The DP dual used will not work for the 118.7 as it is an FSS satellite. The DP dual is for DBS, they are different animals.
There is a repoint kit for the superdish that picks up the 118.7. It's very simple to use.