ok if the hole does not go into oil galleys it will not hurt a thing I am asuming they drilled hole behind where pilot bearing goes. we build 850 hp engines with a hole that goes from back of crank to the front main for lightning about 1 inch dia. you should also use a smaller bolt size they probably saw snout dia and it would weaken to much with a hole that big. 3/8 will work. the Honer
