Sawzall, definetely a grinder. They also have small like air saws that look like a small ratchet. Home Depot and Lowes have a metal sheer which has like two prongs out the front that does the same for metal. But yes those will be good and get you a 4-5 inch die grinder. When grinding AND welding DO NOT welding and grind in the same area for a long time. Weld a bead at about two inches and then move to the other side of the work. When you lay that bead down, get you a body hammer and dolly and hit that weld while it is hot. Just practice some before doing this if you are new at it. It's really not as hard as it seems, just takes a little practice and also there is no way to screw it up, if you mess up it can be fixed. If you plan to paint it yourself then I would recommend a plain 100-150 dollar gun and you can touch up that panel yourself. Either that or I guess you can pay someone to paint it.
Materials:
1.) Die Grinder (4 inch or so)
2.) Body hammer and dolly (flat ones)
3.) Sawzall
4.) Metal air sheer.

That is just some of the things that you should use and it will help you out. Other than that it is pretty straight forward. Good luck and keep us updated!