I think the Park calibration department are all either drunk or smoking something.
Once you get it aligned it’s done and quite simple to do, don’t get the alignment tool.
The base is nice as it allows a variable working angle, I just fixed mine to a bit of plywood with a wedge underneath.
The dishing gauge, in your link, is nice but overpriced for what it is, I think there are other cheaper options for that.
I prefer Spokeys for any wheel building work, the red and yellow will cover most wheels.