Scott,
You are incorrect, you do not set preconditions to change the display order of tool parameters of a model when run as a tool, you do it via the properties with drag 'n' drop.
Watch the video I made below, see how my output parameter from buffer is the first on the tool interface, I don't want that I want it at the bottom, I change the order of parameters in the model property, save, refresh and reopen the tool and you can now see it in the correct location.
Click on the image to enlarge it so its easier to watch