Pull the cylinder liner out which gives you enough space to slide the connecting rod off the crank pin to remove the piston and conrod. The crank should then just slide out. Heat the crankcase in the oven for about 15-20 minutes at 350F and the rear bearing should drop right out. If it doesn't just drop out, tap the crankcase on a block of wood a time or two and it should come out then. If there is a good buildup of congealed oil around the bearing and crankcase it might take a good thump on the block of wood to get the bearing out.