Sounds like you've been doing your homework. -
I'll assume the Ultra will run the motor controller (Gbox) just fine; don't know why it wouldn't.
But, I don't have one, and haven't read anything about them.
One thing you may have a litttle trouble with, is getting the LNBF centered for good Ku reception.
That's only a minor consideration.
Set it up on C-band first, then be prepared for some serious tweaking to get the Ku to track.
. . . or if you're experienced, maybe set up the Ku first? And let C-band fall in by itself?
So, do you have all these pieces right now?
Got some pictures for us?