I think you might be better off creating your wireframes in InDesign.
You can create a master page with common elements, then put each
wireframe on a different page. InDesign CS3 you can import other
InDesign documents as graphics and if you choose "show import
options" when you place the file, you can select which page is
shown. This will update automatically when you update your wireframes
document (I ran a quick test).
One disadvantage to your method (and this would hold true with
Illustrator) is that you'll be placing over and over a file that
might be very large, which will tend to weigh down your document. To
keep files slim, it would be better to make a different file for each
wireframe, or at least keep them down to fewer pages.