How about a scratch built Bipe. Any scale plane that had a round engine is going to require weight in the nose. In this case I had everything moved behind the fire wall I could move. I even have a sub-C 6 volt battery behind the fire wall. It took about 3 pounds of lead in the nose to get the correct CG. I used epoxy and lead shot and floated it inside the engine cowl/ring. This is NOT the way to do it with most planes, the cowl will crack and break off. I made this cowl and the way I set it up there was no problem. Some planes no mater what you do will require lead, in this case it was a lot of lead.