Where should detailed test specifications be stored within the Ration teststudio framework?

Working to an XP methodology, we are often supplied with 'Customer Acceptance Test Specs' which detail areas to be tested. These come in MS word format, and rather than copy and paste them to Test Manager as Test Plans (effectively that is what they are), I'd like to store them in a place where they could be reference easily.

Ideally, I would like to store these specs, then create an abstract test plan in testmanager, and use both sets of documentation for planning/maintenance. Is is Rational TestFactory? Or SiteCheck?

Thanks in advance