If you have all the parts, I can be done... how hard it is depends on nothing really. I just picked up a E30 with a crank sunroof, and the BMW mechanic I bought it off of asked me if I wanted him to do the conversion, and I said no, and he said, "okay, well if you decide you want to do it, come on in, I have a car you can take it off of, and then you'll know how to put it back together on the other car". The main thing is that it can be done, and has been done many times before. If you decide to do it, take notes and pics and be sure to post it up here. Good luck!