Trev,
NOTHING, with the exception of a few nuts and bolts, off the cb350 fits the cb/cl360.
As for how hard a job it is, well that all depends on your skill level. If you are expirenced wrench, then it should be no big deal, if you are a newbie, then it may seem pretty hard but still manageable. Remember to save all the parts. Removing the starter is pretty straight foward, removing the wiring will be a bitch because you have to unthread it from all the passages it is routed through. you could just clip it but then you have to remake the wire if you ever go to install it.
Before you do it, make sure your bike is running perfect. The reason is when you are diagnosing a problem the starter makes it easier to turn over the engine so you can see what you are doing.