I know this is kind of backwoods, but then again I live in Vermont.
If I had your beautiful setup, here is what I would do before moving your heavy amps around. @jjss49 if you think this is a bad idea please chime in.
With your preamp, amp and CD player on, I would set the preamp to CD mode. I would turn my preamp up to about 1/10th volume (any VERY low setting). I would GENTLY tap on the top of the preamp cover, then CD player cover, and then sides of the amps. If I did not hear the dreaded (thump) or a tube rush sound I would repeat this, increasing the preamp volume, in small increments until I was at about one half volume. This should take in total about 25 seconds.
If you do not hear a "thump" through your speakers when taping on your units I would say you have nothing to worry about regarding microphonics.
In my layman's way of explaining it, microphonics are the result of anything vibrating a tube sensitive to microphonics, whether by picking up speaker vibrations, taping the top of the unit having the microphonic tube or any other movement.