Bajadesigns has a new dual sport kit that concentrates most of the componentry behind the headlight cowl, which can be easily removed and replaced with a stock unit. The front turn signals appear to be mounted to the cowl. Not sure about rear signals though.
For rear signals, consider those tear-drop shaped 'marker' lights mounted permanently to the fender instead of signals on stalks. Sure, the marker lights are not easily detachable, but they are out of the way and very difficult to damage in a crash because they do not get hit. And they are cheap to replace if they do get damaged.
In CA, your rear signals are supposed to be 9" or more apart, so check your local vehicle code for legality.
Thanks, I kind of pictured some kind of a spring loaded twist-lock type deal you could just pop on a pop off when going full-on off road. The small teardrops would work too and not be too obtrusive. (is that a word?) :eek: