I don't know anything about the Zaino AIO, unfortunately. Based on the Zaino website, it looks like you don't need ZFX if you're topping AIO with one coat of Z-5 or Z-2.
I'd recommend: wash - dry - clay - wipe down with IPA (some people prefer a re-wash instead) - polish with your 7424 using the Menz line of polishes - wipe down with IPA - Z-5 with ZFX (by hand) - buff off (by hand) - Z-2 with ZFX - buff off. I own but don't typically use Z-8 after sealing because I just don't see the claimed "additional gloss."
If you've never done this before, you're in for a surprise at how much work it is, especially if doing an SUV is your first project! You'll be sore the next day and quickly understand why good detailers charge several hundred dollars. But it's a labor of love on our cars, and you'll be looking to do it again soon enough.
