On 2022-01-04 7:07 a.m., Micah Salb via groups.io wrote:
> I'd be inclined to look for two shims of a reasonably slippery material that I
could put under the bookcase to increase the ability of the floor to move
despite the bolted-down and heavy bookcases.  Maybe just a pair of stainless
steel plates?  I don't know if it is necessary but. . . .

I'd go with my default shims - discarded compact discs. They come 
pre-drlled and are a consistent thickness.

FWIW

Don

-- 
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