I can see why you are using 1m dishes to get DishNetwork service in Mexico.
I'd use DishPro LNBFs, and feed 'em through a DP34 DishNet switch for your Dish subscription.
The FTA receiver can plug into the DP34 just fine (use diseqc commands), but as described above, won't do much.
The solution would be different for DirecTV, but again, their and DishNet's LNBFs are circular and pointed at the wrong birds for any actual FTA reception.
(and set for the wrong portion of the band, too! )
Likewise, you do NOT want to motorize/move any of the dishes used for your subscripton.
The subscription receiver check with its respective satellites behind your back to get guide and update info.
If it finds one of its satellites missing, it doesn't handle that very well.
Other than repeating what AcWx and Turbo had to say above, I think that about covers it.