While on this subject. Can anybody recommend the best way to change my gas bottle size from a 2.75kg to 4.5kg. The boat was designed for a 2.75 bottle. On my B42 2000 its sits on a premade locker aft, that is 340mm high (same size as a 4.5kg bottle ) but not wide enough to take a 4.5kg bottle. It narrows in the middle. The front of the locker is okay to take the bigger bottle. Anybody overcome this. A 2.75kg bottle is twice the price of a 4.5kg bottle for nearly half the gas.