They are NOT supposed to touch. What people do not understand with our suspensions is that the strut rod at the top will move as you turn the steering wheel due to the inherent camber and caster - hence if you try to clamp it hard to the strut towers, you'll eventually fatigue the rod and break it.
Trust me I know what I'm tlaking about.
Joe - it helps to have someone who KNOWS how to install wheel bearings (me), install your bearings for you.
