anyone have any good tricks regarding removing 50-plus years of rust?

im only concerned with patching the worst areas of the pan and im not finding replacement pans (52 88 4 door) ive been sanding and grinding and after 3 hours i have one half of the drivers front done (whew) im considering sandblasting. anyone had any experience with this? something else maybe?
thanks!!!!

 

What about using a chemical rust converter? You have to clean around the areas that are too thin or actually holes to accept welding patch pieces in I know but for the rest of it just use the chemical stuff. It stops rust and seals the metal. Then you can prime and paint and be done with it.

 

thanks! any brand name you recommend? ive been sandblasting today and its working but a bit slow.
thanks again!