Wow, looking back on your posts, I'm surprised it's been this long before you got one. Based on your prior posts, I would have expected to see you with a Mk2 a long time ago. You sure did some long-term lurking.
Well, I've personally seen at least one empeg looking really nice in a TT dashboard, so I know it can be done. Whether or not it will be easy to integrate with the factory amp/speakers I don't know. I'm sure you've checked out the Installation section of the FAQ at riocar.org by now, but most importantly, if you have TT-specific questions, you might want to ask on a TT-specific bulletin board. Just say you have a standard aftermarket stereo but with only line-level outputs, and you want to know if there is a line-input converter available for the Bose system in your model of TT.
Looking forward to hearing your impressions of the product when you finally get it. After having waited so long...