the way i did my last top end was easy.put the rings on the right way,put in the inboard side c-clip in piston,insert the piston the correct way a little bit into the bottom of the bore,enough for the wrist pin hole to show.next put wrist pin in piston with a little 2 stroke oil.put c-clip in on out side, slide the jug the rest of the way down.repeat other side.just dont forget to put base gaskets on and rags above crank to save from a lost c-clip.before i put the head on i like to put a little 2-stroke oil in the clyinders and turn it over a few times to get the rings lubed