RE: need help removing crankshaft.
Ok, follow this procedure;
Make sure the piston is at the bottom (BTC. Bottom dead center).
From top of the engine, stick a small zip tie into the exhaust port & turn the crankshaft (you will probably need pliers) so that the piston pushes on the zip tie, which will in turn will push the liner up. If the liner won't budge, then you'll need to heat the engine in the oven & try the procedure again before it cools off too much. Careful not to burn your self.
Once the lip of the liner has cleared the top of the crankcase, lower the piston and remove the zip tie. With a small flat blade screwdriver, carefully lever out the liner a little more so that you can pull it out with your fingers.
To remove the piston, turn the crank until the piston is at the top (TDC. Top dead center). Turn the engine upside down & with your finger you should be able to pull the rod off the crankpin. In very rare cases, finder power may not be enough to pull the rod off and you need to resort to hooking a small zip tie or cord around the rod & using that to pull it off.
To install, reverse the procedure.
*Edit*
Since you have the piston/rod out of the engine, you may want to take the time to polish the varnish (brown stuff) off the top of the piston. You can use silver/brass polish & don't over do it, just enough to get the brown off.