Yeah it is possible, would I take the time and money to have it run RIGHT...NO
The problem with retrofitting a turbo is that you have to have custom pipe bent, find a place to put an intercooler and plumb it, and also you would probably have to dyno tune till the end of time to get it right-among other things. That's not even mentioning the fact that you could easily blow up your motor with slight imperfections in the system.
To make a long story short, I wouldn't reccomend retrofitting a turbo because it is WAY too expensive. If you want a turbo system that will probably work and be a lot more plug'n'play(not easy still, but relatively easy compared to retrofit) wait for Chris Hightower's system which will be out by January hopefully(fingers crossed)
HTH