Embed linked Visio Obj into Word, rotate 90 degrees

The Situation:
Large technical manual contains 1000+ pages, 30 of which are flowcharts in Visio (two visio files with several pages in each). Word doc must print in portrait, Visio Doc is in landscape. I need to import the visio images into Word, linked so any changes will be reflected in the Word Doc (it is expected that this document will be regularly updated), BUT in order to fit them onto the page and accomodate the fact that the Word document will be printed as a book (ie, mirror margins), they need to be rotated 90 degrees. Embedding the charts as linked images is no problem, but Word will not allow me to rotate them. Putting them in separate, landscape sections in the Word Doc is also not doable, since the length of the document varies (several different versions can be generated and printed by end users) thus fubaring the margins if they have to be manually set, and also messing up headers and footers. In short, I need to be able to preserve both data integrity (ie, use a linked, embedded Visio object so changes will be visible in the Word doc), and also preserve the formatting (the objects must be rotated 90 degrees so I can fit them onto a portrait page). I have considered exporting the Visio pages as .gifs, but due to the frequency of updates, this will necessitate a lot of maintenance work on what is supposed to be a self-generating document. Once I've finished setting it up, it will be maintained by people with limited computer experience - if they have to faff around with exporting pages or the like, they'll get it wrong.

Asking a lot, I know, but if anyone knows the workaround to this or can suggest a VB solution (I can do VBA, but so far not in Visio, so code examples would be great ;-) ) then that would be cool.

Many thanks,

Ganeth