When I got my C1 from Tsun in Canada, took 8 days to get everything right so I could ride it. If you have a China bike, and the factory worker screws it up it just keeps going. I remember the insides of the SS chain guards where razor sharp. Have to do alot of work on these bikes, had to shim the engine mount with SS thin flat washers cause it was loose in the frame & replace bolts,etc.
First tools I got that I did not have already was a dremel electric rotory file and a $40 metric tap and die set, that has everything, easy outs and drill for them, spring loaded center punch and all, use it almost everyday. I tap every female thread on the engine & other places, and replace the bolts w/ M6 x 1.0 x how long socket/allen head grade 5, 8.8 bolts. I have some SS M5 x 0.8 x 50mm bolts hold some of my carbs to the intake manifold, and adding a boost bottle helps also.
On splitting the cases, most have 2 or more small pins keeping everything inline, try prying them apart with wooden or plastic piece that is thin and knife shaped edge. Make sure all the bolts are out of the cases and you might want to find out for sure how they come apart.