Help Need Serious Advice

[70GranCoupe]

My car has pretty bad rust on the pillar at the base where it attaches to the rocker 37 years of being in the Northeast. I have the entire firewall/cowl section from a donor car, cut through the rockers up to the A pillars. This section in the donor piece is in great shape. As you can see from the pic the cowl end piece has already been removed and needs to be replaced from the donor car as well plus a lot of the cowl behind the MC Booster. I am new to this and looking at the way that this pillar is attached to the rocker looks pretty intense. There is a lot of body panels coming together there and drilling it all out looks like a nightmare. My question is if I were to go this route what would be the best way to do it?

Also, any other suggestions about how to repair this?

I have heard everything from don't mess with it just POR-15 it and no one will see it anyway. To thinking of maybe just trying to replace the rusted section at the bottom.

I dunno looking for options and advice on how to get there!
Thanks! Sean

[Killer_Mopar]

I wouldn't replace the whole thing because I dont see it being structural and it isnt going to be seen. I would grind out all the rust and weld in a couple small patches, which would mostly consist of the weld. Then I would probably just grind them down and seal them, if there is any chance that the patches are going to be seen then I would dress them up some more.

[ShelbyDogg]

I would cut off the lower half of the inside lower piece, fix any rust on the bottom, then put in a patch from the donor car. That will hold it all together when you cut off the lower half of the ouside piece and patch it. It's up to you. Just don't support the car from the very front before you cut that off.

Rob