Linked Materials, but Separate Texture Maps?

[hnf]

I have a common problem in my work flow: when rendering a wooden chair (for example) I have 7+ individual models (pieces of the chair) that I want to be wood.  But I will need to rotate the texture map on each one individually to get the wood grain going the right direction. So I unlink the materials to adjust the mapping separately.  But then if I want to adjust the color of the wood grain or set up a multi-material I have to go and adjust it on each of the 7+ models.  Because if I link them again, the mapping is lost.

Is there anyway to have the Bump, Specular, Diffuse, Opacity linked together, but the mapping remain separate? 

If no, is there an easy way for me to copy changes (such as adding multimaterial colors of wood etc) from one part to the next without resetting the mapping?

Thanks so much for any help you can provide!