Start with a pair of McKesh mirrors.
http://www.hensleymfg.com/mckeshmirrors.html
About ~$150, and they are the best out there. Once you get them setup the first time, it takes about 2-3 minutes to put them both on, and about 20 seconds to take them off.
That should give you enough coverage. If you still want more, then you can talk about wiring up a camera in the rear of the TM, but that's a bit more complicated and expensive endeavor. But it has been done.
I bought more convex mirrors as well, and wouldn't be without them.
Dave