* One thing that has been reported about them, the metal grille are held in place in a 'slot'. (To remove them, you take off the top or bottom(?) trim piece/s, then slide the grille up, out of the 'slot').
As such, when in place, they are pressed forward, by foam bits, stuck at strategic points (e.g. the lips of the tweeter). The foam is dry rotted, so no longer presses, so the metal grille may rattle with use.
Expect to replace the foam bits so that this is not an issue. (or, just remove the grilles if that is feasible).