First attempt at real bodywork. Tips?

Those a pillars are layered as you know.so at our shop we would start with that inside piece by the dash.just jam a piece of scrap metal behind it and weld it from the inside so the weld would be covered when you attach the outer piece. Once you got the inner pieces looking factory primer the inside cavity and lay the outer piece on top. Trace it with a sharply where you want it and then trim the car to fit the ppiece.it's easier then shaping the piece and shooting it across the room lol.The tighter the fit the easier it will weld. If using a tig get some .020 wire .it wont shoot holes in that thin metal .put a tack every 1/2inxh or so, and clean it well with a wire brush often as you do it. The only other advice I have is to keep an eye on the urethane around the windshield. It doesn't take much heat to make that stuff melt and drip where you dont want it. Oh ya put some seal seal around it after so it doesn't ever leak again