The reed valve plate is held in place by the 2 long screws that go through the carb and into the crankcase. With the carb off the plate will just lift off. That nut holds the reed valve itself: do not undo that nut.
Don't know of any way to reinstall the bottom end bearings but to split the cases.You can use grease to hold the bearings in place and then flush out with premix after everything is reassembled.
Thought I had posted about reassembly trick on these saws. For reassembly, install the piston and rod into the cylinder, goop up the cylinder bottom plate and gasket and install them, slip the crankshaft through the rod, goop up the bearings and install those. At this point both pieces of the case gasket need to be in place, I use Yamabond.
With everything held steady, install the crankshaft / top end onto one case half. Then install two cylinder bottom bolts into that case half, not fully tight, but tight enough to keep the cylinder in place and allow the other case half to slip over the cylinder bottom gasket. This trick keeps the rod from moving sideways and freeing those bearings. Then install the other case half.
For these saws, if I'm changing anything out in the top end, I use popsicle sticks jammed in through the hole under the reed valve plate into crankcase on both sides of the connecting rod to keep it from moving sideways and freeing those bearings. Then the cylinder can come off. Also learned the hard way about those bearings.
