My brother and I did his 22 Buick roadster. This body had NO structure what so ever, we are talking sheetmetal skins nailed to the wood.
He designed most of it and did an amazing job. The first thing you have to remember is not to get locked into any particular metal size, use what makes sense at the particular place you are working on. Also, only use the wood that was there as a "guideline", don't try to duplicate it, you are REPLACING the wood right? If you wanted it perfectly the way it was you would be using wood.
On the larger pieces like the hinge pillers we used 3x2 eighth inch wall tubing. We made a template to the shape of the body with poster board and then using a band saw cut the outside of the tubing to match the body. Then, welded a strip of metal down the edge of the tube, makeing it a tube again. We left the inside straight, so all the way around the door all the pieces are straight. On your taller 32 doors, I would think about bending the tubing or after cutting it like we did, weld in your strip, then cut the inside and do the same. You can end up with a piece of tubing exactly the shape you want.
There were areas we only used angle iron, there were places where 1 inch tubing was used. Just use the right steel that makes sense. I have to tell you, we could pull the interiour out of this car and show it, the stucture, all painted nice looks that good.