Selecting Mutlipe surface

Is there a way to select more than one surface to shape a sheetmetal part to? I am in the process of drawing a boat and i want to draw my transom in to fit the side sheet,chine and bottom plate. Ive tried merging entities to create one body but because the sheetmetals are differant thicknesses its not working at least i think thats why. any thoughts

Dave

SolidworksSheet Metal