I recently used two pieces of sheet metal to help install my 4 carbs on a 1976 CB550F. The principal here is to create a trough for the carbs to travel in. Do this by cutting two pieces of light guage sheet metal to a size of 3 inches by 12 inches. Hold one of them in front of the intake manifolds and the other in front of the air box intakes. Then have someone else to slide the carbs in between the two strips of sheet metal till they are lined up and in place. Then simply slide the two pieces of sheet metal out, pop the carbs into the intake boots and the air box boots and Wa-La, your done....................