A lot of people with many years of experience are giving you some very good advice. You'd be a fool not to listen to what they say an put their suggestions into practice. The biggest mistakes novices make are: cam too big, carb too big, heads too big. Bigger is not better! Bigger is dumber! You have to think of an engine as a system of interrelated parts that must work together efficiently if it is going to perform to expectations. Mistakes are disappointing and expensive.