Complex sentence: A proposal was made in 1942 to convert "Vanguard" to an aircraft carrier and the Director of Naval Construction said that doing so along the lines of the would present no major difficulties, but would require six months to redesign the ship.
Split into simpler sentences: A proposal was made in 1942 to convert "Vanguard" to an aircraft carrier. The Director of Naval Construction stated that doing so along the lines of the would present no major difficulties, but would require six months to redesign the ship.