Dimensioning Between Parts?

Hi all,

I've been helping a colleague get started with Solidworks and he hit me with a question I couldn't readily answer.  Is it possible to link dimensions between separate part files?

We've got a couple simple flanges and a gasket we're working with, and I'm trying to find a way to link the bolt hole profile between them.  I know this is possible with the equation editor and/or design tables if you create the parts virtually within an assembly file, but I have never tried to link between external part files.  All my investigoogling has pointed toward creating entirely within an assembly file, so I figure I'd come here to see if there are any other methods.

Thanks,

-Sam

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