I guess I kind of misspoke. I didn't take the time to make or buy anything that would give me an easily repeatable way of turning 20 degrees which is why I was using the steering stops. Although it sounds like marks on the garage floor could work very well. I also think I might trust a bubble level type device more than my cheap digital angle gage. Sort of like stringing the car for toe. I looked at a relatively cheap laser to possibly use and the accuracy was only like +- 1/8" in 20 feet. I know I can get closer than that using a string.