You will need to remove the front bumper, both front fenders, and probably the hood(ok you don't have to but might as well. The inner fenders(part you see inside the engine bay will attach to the core support. If you do this do a lot of measuring, Make sure you keep the distance between them the same. I would also measure the distance from the top of the core support to the ground in several places to make sure you don't have it to high or low.(with the body panels off so there is not a weight difference) Where there are intersections of panels(not fenders, but welded panels) take pictures so you know how they align. Measure a whole lot, more then what you would think and write it down. They make a spot welder removal tool which is nice, get it with a few extra cutting bits, you will pre drill all the spot welds with a small bit then use the spot weld cutter to remove the welds. once the core support is off grind all the spot welds flat(make sure to cover painted areas and glass metal fragments will embed them self in those) Once they are all smooth apply some weld through primer to all the bare metal. Pre drill or punch holes about the size of your spot weld cutters dimensions in the new panel and tack it on there. Measure, then measure again. Then start filling in your holes. Move around and don't put to much heat in one place. Heat will do funny things and make the metal grow and shrink in weird ways. Don't move around in a circle. I did one in the dark in about 3 hours. Panels fit fine, and it held up well, until the truck was wreaked again.
But to warn you, i have a decent amount of experience doing this...
