This post will focus on the removal and moving of the b-pillar to fit the extended doors and then the fabrication and rebuilding of the rocker panel structure.
The first step was the removal of the complete b-pillar from the original rocker structure. There wasn't much left of the rockers, but the pillars were in decent shape actually.
I added more square bracing (which I forgot to mention I had added previous to cutting the roof off)
After much measuring, fitting, testing, etc. I place the b-pillar in the correct location. From the additional bracing I actually made temporary mounts that I could bolt the b-pillar to while working on rebuilding the rocker panels. When needed, I could just unbolt the pillar out of the way and bolt it right back into the same exact position later.
Here is a picture from the backside showing the temporary bracing / mounts to bolt in the pillar (two bolts at the top and two near the bottom)
Once the pillar was in the correct spot and the door was closing and latching good enough I started cutting away all the rockers to start rebuilding them. Here the outer skin is removed, and it shows just how bad the inner structure was.
Progressing further, the inner structure of the rocker is being removed here. Technically there is a 90 deg. edge from the floor and a second inner panel that creates the "box" structure of the rocker panel.
Here you can also see how the b-pillar is actually just "floating" in mid air only bolted to the temporary bracing inside.
Even with the rocker panel completely removed and the b-pillar just "floating" in mid air, the door still closed and latched just fine.
The next portion of this update is about rebuilding the rocker panels.
This simple drawing shows the original construction of the rocker panel (upper left drawing) This shows how the factory "pinch weld" was done on the bottom.
Note from left to right:
3. The outer rocker skin
2. The inner rocker structure
1. This is actually the edge of the floor, which I had to replace as well.
The drawing on the bottom is how I changed it up a bit. I prefer not to have a visual pinchweld. So I basically just folded the flanges of part 1 and 2 back onto each other and plug welded them as normal
Again 1, 2 and 3 are the same as described above. Here you can see how the floor edge (1) and inner structure (2) create a nice strong box structure.
The first piece of the rebuild is piece 1 (the floor edge) I trimmed back the original floor and butt welded this piece to it.
This piece also follows the floor braces (thus the "kink" or bend in the part roughly in the middle)
Here is a view looking down the first piece installed. You can see the "kink" in the part as it follows the original floor braces underneath.
The next piece fabricated was piece 2 (the inner structure) This piece also has a "kink" but this time the kink is at the b-pillar. This is done so eventually the rocker panel / door edge structure is straight in the door opening and follows the edge of the door shell bottom.
This picture also shows an additional "bridge" or stiffener I added where the b-pillar mounts. This will help strengthen up this area as well as spread the load out just a bit more.
With piece 1 (floor edge) and piece 2 (inner structure) installed I was able to bolt the b-pillar back in to see how it fit to the new structure. Lined right up!
This picture helps show the "kink" I was referring to. As you can see it's straight from the a-pillar to the b-pillar, then kinks in to line up with the original structure at the quarter panel.
This is a good picture that shows how I "keyed" in the rocker structure just as the original. This is the structure at the rear quarter panel. It slipped right in and I plug welded it all together just as original (It's the same at the a-pillar as well basically)
While doing the driver's side I made up all the "mirrored" parts to do the passenger side as well.