They should be just to where they pop, pop, pop a little when you tighten them, from our experience.
We do not actually torque them because of the reseating of the center cylinder when you tighten the stem bolts.
the center stem is parting, so it must be pulled back together.
The issue will be gone if you do not stretch the bolt stems back out, by taking the plate up when you tow.
Thanks for noticing and we hope this diverted a problem for you!
BCB