It all depends on your skill level in welding and the welder you choose. There is a lot of butt welding with a skin, and plugs with a full quarter. Panel warping would be my biggest concern.
You can go thru my pics as Bjorn posted and check out this vid from Youtube, it is a 3 part series. I watched it 8-9 times before taking the plunge....all in all, was not that difficult for me, even though I had never done it.