We installers all use one of these,
Suunto Tandem | Suunto
which does what Joys rig does basically.
One thing to realize is that while you do need the Southern view open it will not really be at the angle you think.
The dish points straight up a lot more than you imagine it will and I have only had a few times where I could not get it Dialed In even though a quick look can make it look like it will be a problem.
I ca pretty much get them aligned without any aid if I am busy with them but if I don't do one for a while I seem to loose the touch.