Another thing to pay attention too is the piston and rod assembly.

A lot of times--the side of the rod that faces forward and is closest to the crankshaft counterweight will have a small chamfer or bevel in the rod bushing.

This is because the crank pin is not machined to a perfect 90* angle right where it comes out the back of the coutnerweight. The crank pin will have a very small shoulder on it. It is necessary to machine a slight bevel in the rod bushing to ride on this part of the crank pin.

Just make a note of which way the piston/rod assembly is facing when you take it out. Some pistons have an arrow or other indication mark on the top. This isually points towards the exhaust port.

Bearing removal:
Strip the engine down to a bare case. Toss it in the oven at the lowest setting you can get. (helps if your wife is out shopping when you do this) Wait about 10 or 15 minutes.

Remove the case with an oven mitt or heavy glove. Turn it up so that the rear bearing is facing straight down. Tap the case down on a 2x4 or other piece of soft material--so you don't damage the case. A couple taps--and the rear bearing will fall out.

Front bearing. Hold the case in the same position. Get a wood dowel thats close to the size of the crank. Insert dowel through the back of the engine and stand it up on end. Hold the dowel in place solidly against the front bearing. Tap it down a couple times on the 2x4. Front bearing will pop out.

Bearing installation:
Freeze bearings for at least 1/2 hour in a plastic bag. Stick them in the freezer.
Heat case in the oven again for 10 or 15 minutes.

Remove bearings from freezer and get them ready. Get the case out of the oven and drop the bearings in. Set them in the case with a wood dowel and a couple light taps from the end of a medium screwdriver. (NOT A BIG FRIGGIN' HAMMER!!)

The wood dowel should be big enough that it makes contact with the outer ring(race) on the bearings. You don't want to exert heavy forces in the inside ring(race) of the bearings. Thats a sure-fire way to ruin a bearing.