Couple things I can offer is first to get your sheet metal welding process down with your mig. I found the best way for me was to use compressed air to cool the piece down right after you do an inch or so bead. Be careful though, I got a 3/16 size hole in my knee from setting the gun down to fast...
Other thing is get ready for some fun in trying to make those inner cowl pieces fit. I had to cut the bottom off mine, re-shape them to fit and then weld them back on.
