When I first got my GTS, I could only see the rear fender bulge in my right outside mirror. It seemed like the car had a HUGE blindspot. I thought my rear view mirrors were about useless at that time, unitl someone on this site turned me on to a different way to set your outside mirrors.
I start adjusting my mirrors by looking at the interior mirror, and noticing the extreme left and right field of view. Note reference objects to mark the limits of vision. (Tree, car, mailbox, et al)
With the exterior mirrors turned way out away from the car, I slowly bring them in until the reference objects just come into view, with a slight overlap.
This method gets a little getting used to, but reduces my blind spot drastically. At first, its a little un-nerving to look in the outside mirror, and not see the same field of view that you do through the interior mirror.
There really isn't any reason why you need to see the same thing in your interior mirror as you do in your outside mirrors, anyway. Why not use your outside mirrors to your fullest advantage?