As far as the fix holding up, so far so good. I'm going to put about 1400 miles on the car in the next week, so if there is any bad tire wear, it will show up.
And yeah, the "Hightower Thumbs" were intentional.
Doubtful. Jack up one corner and remove a tire. Crawl under there (USE A JACKSTAND FOR SAFETY) and you can get a good look at the arms where they go into the subframe. Not much room in there, and you can only get to one side of the rubber bushing anyway.