Use the newest trinity build, and you dont need to edit any settings.
It will figure out what spec you are using when it loads up. Works for every spec that actually will work.
I switched Aquila with a Crown of the Primus, since you can't force trinity to spam spectral blades to keep your arcane above 90% most of the time. This also gives a fair bit more damage. I've been farming GR66 nonstop without a single death. It can definitely push higher though, I just need better rolls.