<VV> Help with rust repair

[Sethracer at aol.com]

You can all laugh now at a Californian asking for rust help. I am beginning  
the body work to bring the Corvair/Stinger up to snuff body wise. This is a 
race  car, not any kind of show car. But it has a typical case of California  
windshield drain rust. It also has a similar afliction in the rear  window area 
on one side. I have pulled both windows and worked a bit on the  rusted areas. 
I cleaned off the sealant around both windows. Amazingly, all of  the clip 
mounting studs, except one, were in great shape and reusable. It  will need new 
clips, but the studs were in great shape. I have removed   most of the loose 
rust scale. There are several areas where material will  have  be added to 
return the "systems" to normal. (holes in the body) Where  there are holes in the 
metal, should I ground out the bad stuff and weld new  sheetmetal in? I could 
coat the remaining rusty areas with POR-15 before  painting. What kind of 
welding should I use for the holes in the sheet metal. Is  MIG applicable or can I 
TIG in the replacements. I can use an Acetelyn torch to  de-oxidize the area, 
if that is a good plan. And suggestions on how to  proceed? 
 
- Seth Emerson