Well, what I WAS going to do was mount the DPP-Twin half-off the mount (119 side of LNB on the 110 side of the mount), and the Single/Dual on the 119 side of the mount. Would probably need some wire ties or the like to hold it together.
Of course, now that I've got a Dish1000 sitting here waiting to be installed for a customer, and another one arriving in a couple of days, there's just no point in screwing with it any more (for me - you guys feel free to continue - it's all good!).
Anyway, whether you can get 119/129 on a Twin with good signal will depend on your location. I forget which way it goes, but farther north (south) separates the focal center, and the other way brings them together. There was a thread about it some months ago.