forlorm22 if your going to get the os cvr you need the one with the standard crankshaft http://osengines.com/engines/osmg2104.html
that is the exact engine you need. I recomend changing to the single speed direct drive transmission instead of the twospeed(thats what i have and the thing still flys) Fot the clutch I recoment the hpi heavy duty 14 tooth bell(13tooth you need to run crappy bearings not worth it) and for the clutch shoes I got the hpi nitro 3 shoes http://www3.towerhobbies.com/cgi-bin...?&I=LXCFR3&P=7
you will need this pilot nut if your going to run the nitro 3 shoes with the single speed or this one if your going to run the 13/18 bell for the 2speed http://www3.towerhobbies.com/cgi-bin...?&I=LXM721&P=7
now for your drive shaft and diff cups issue on the rear the hpi mt2 18ss heavy duty dog bone and drive cups fit right in or you can get the mt218ss diff cup and a GPM cvd from ebay for the mt2(I have one and its working good still) Im not sure if the front one will work
When I pit the cvrx 18 and the single speed transmission in my tsunami I had to trim a little bit of plastic by the throttle servo just to make a little room to get the right gear mesh no big deal. good luck man if there is anything that i missed let me know.