shipyard question about editing existing ships

I searched around for this, but I could not find it. If you want to upgrade only one part of your ship, say weapons, is there a way to do just that without having to go and place the engine, defense, modules, etc. all over again? In other words, let's say you've advanced your beam weapons a couple of levels, but you haven't gotten any other tech. When you go to upgrade your ship, you have to place all the engines, modules, defense, everything all over again just to replace a couple weapons. Is there any way to avoid having to place all that stuff again every time? Thanks.