ok....lets give some advice on how to properly butt weld a panel. first cut the rust out of the car you intend on repairing. take the metal you cut out to the new sheetmetal you intend to make repairs with and size the panel up. take your new panel to the car and check for fitment. make sure you can place the panel inside the area you are going to weld it into. you should have a slight gap around the panel for penetration purposes. if your in doubt, cut a short peice of the mig wire your going to use to weld the panel and take it to 2 redge. a right angle of sorts. for example you should be able to slip the wire into the top edge and run it to the side edge and down. you should not be able to slip it all around. once you can slide it on 2 edges your ready to tack the panel in place. split the difference of the gap and make sure the new panel if flush in the hole you plan on repairing. tack it in place and begin to work you way around the panel flushing it with the cars panel until you have the panel tacked completely around the edge. then begin to tack the panel every few inches skipping around until the panel is fully welded. if you have a large panel, you will need to pay attention to the heat you put into the metal. if you cant touch the panel with your hand your too hot!!! sheetmetal will warp if too hot and it will take way too much work for the average hobbyist to get it back straight. just be patient and you'll get it done!! remember it will cost triple if you over heat it so walk away if you get in too much of a hurry. you'll be happy you did!!!

hope this help those of you looking to do a butt weld!! remember walk away if you cant touch it. its waited 40 years for someone to restore it, 4 more hours isnt going to send it to the scrap yard!!!