The only special tool you really need is a flywheel puller. If the crank hasn’t been slip fitted, you will need a simple puller to separate the case halves. If it has been slip fitted, and most kart engines have had that done, simply whack the end of the crank with a rubber mallet and it should fall apart. Buying a Honda manual would be a big help because when it falls apart, lots of stuff goes rolling on to the floor!