That's a good lookin' cow right there!
Great tutorial Matt. You might want to take it easy on Woodward and maybe go up as far as Long Lake to see if you've got any vibration from the wheelcovers being out of balance. It should show up by the time you get to 50mph.
There are machines to balance a wheel & tire combo on a car, but I have absolutely no clue as to how those wheel covers were dynamically balanced. I guess if you do find a vibration and can narrow it down to one wheel, just try re-orienting the vanes by one bolt hole and try again?