patch panel

I thought this might be a good topic for board here , and may become useful in the future for others. When making a patch panel somtimes it is very easy when the area is flat like a truck bed or a minor curve like a trunk lid. But what about those hard to make compound curves that seem to the target for rust , such as around a windshield . Its easy if you can buy the replacement panel but if you have to make it and don't have an english wheel or the other high dollar tools what then. I don't have those tools and have had to resort to the old vise grips and torch. By clamping a peace of stock to the area in question for repair and heating it , then tapping it into shape or at least close enough to get the correct shape. Then use this patch as a template to cut out the panel to be repaired ( remember to consider the width of the cut off tools blade or the gap will be to big to weld). Once the panel has a few tack welds in it can be formed. Are there any other kool tricks to making patch panels?