Get the Crank,Bearings,Seals pack that Linda suggested. If you go with te 65 metra kit you will not be dissapointed. You will need a Pipe also....May i suggest the Techno Boss...best bang for your buck if you ask me.
While you have the Case apart to replace the crank do yourself a favor and match the case to your kit. If your not sure how to do this there is information in the Wiki and also video on YouTube about it. Down the road if you feel up to it the 65 metra has tons of room to open the transfers on the kit which will help you reach higher speeds if done correctly. Making sure to match your intake and exhaust to your kit is also a good idea because it will let everything flow smoother.