Originally Posted by Fred Hubbard

I've never been too concerned about marking the collars and then trying to make sure both markings end up in the same place. What I have found is that if your car is balanced left to right then the collar will have the same general amount of space between it and the cap. So although I do look look at this space and verify that there isn't a huge disparity between both sides on each end of the car when there has been naturally something is wrong. To have the collars within a half turn of each other is good. Also I recommend to get into a habit of checking your shock lengths to ensure they aren't too far off. I usually check the shock lengths when I change oil or freshen up my shocks.