I think this might be what you're looking for:
http://www.rattlebars.com/mtz/invisible.htmlI considered doing this with mine, but ultimately decided to install it as prescribed in the directions just because I was a little hesitant to install it contrary to convention and have trouble disengaging it. Now that its installed and in use, I can see its no big deal to turn it around. I don't use mine much, but its nice to have to give your throttle hand a break on longer rides.
Make sure you understand the directions regarding how to create the proper thickness of rubber spacer. I didn't until
after I spent a bunch of time modifying the thickest rubber gasket to fit.