Link Configuration to a different part dimension in an assembly

I have an assembly with several parts. I would like to have Part A change configurations based on a dimension from Part B in the same assembly.

Is there a way to set an equation or some other linking tool to drive the configuration of Part A from a dimension from Part B? I would like to keep Part A the same and not make any changes so I can do this.

Thanks for all of the help!

SolidworksAssemblies