Anyone had experience working on A-Pillars?

Hi guys,
  I just bought a 1967 fastback and - for the most part - this sucker is CLEAN! The area that isn't is what I'm writing about. There's no rust on the thing anywhere...EXCEPT a nasty patch about 5-3/4" up the A-Pillar from the upper door hinge on the passenger side.  I was thinking about blocking it just to see if it'll go away, but I can already tell that it is eating deep into the metal.  Does anybody have any experience working on A-Pillars?  Ideally, I could cut out the bad piece, fab a cage that could join the top and bottom sections, gusset the joints, fab exterior bracings to wrap around the whole column and stitch the thing up. But, I'm concerned about the structural integrity with this approach.  One thing I'm definitely concerned about is cutting through the A-Pillar without having the car properly braced. I'm concerned that the areas that the passenger A-Pillar supports will sag and end up twisting the other load bearing members.  Any ideas?  Also, which assembly manual would contain information on working on the A-Pillars: The Body manual? The Weld/Sealant manual? The Chassis manual?