Re: Splitting the crankcase
Roger like to tell people everything he knows. You should not worry about stuffing cases or custom porting unless you crave speed and broken parts.
Splitting the cases is not too hard. Just use taps with a hammer to drive out the clutch shaft (can come out either side) and then split the case by tapping the crank while holding the case.
The mains often stick on the crank and come out with it, so you may need a small puller to get the bearing off the crank. DON'T try to pry it off with screwdrivers. This is a great way to bend the crank. Remember, cranks are SOFT everywhere but the bearing journal.
I ALWAYS use a scotchbrite pad on the crank journals until the mains slide on and off easily. This makes re-assembly MUCH easier. Drive the mains in the cases with a socket and hammer, then slide the crank in one side and assemble. If you have to beat it together, you stand a good chance of binding and screwing up the bearing bore or case or bending the crank.
If more is better, then too much is just enough.
If you can't afford it, build it yourself.