The bun style are easy as to take off.
The 3L carbys are pretty simple. You probably know this already, but whatever you do, don't try to remove the needle without removing the middle of the carby (removed via 2 external screws).
Otherwise you will snap the forked peg that controls the needle (its name alludes me).
My one's de-compressor line had a crack in it, fortunately I noticed before i put it back together. Sometimes just those simple things.
