Someone with some knowledge who has rebuilt an engine before..
It's not just a case of bolting some parts together and go racing....
you have to know about clearances, and balancing, and how to achieve those clearances...
I could tell you to go buy an xyz crankshaft and rods, but if you have the wrong pistons, they will hit the heads or a different piston will never make compression..
find an older guy who's been building these for twenty years and sit under his tree.. grasshopper.....