What Carl 52 sez..
1.0 Consider the floor pans first. The cab is attached to the frame at 4 fixing points. You want to ensure your new floor pans align with your under pan mounting of the front 2 cab mounts. This is an important reference point. To accomplish, I suggest to place your cab back on the frame, installing the 4 cab mounts with new rubber bushing/pads prior to removing your floor pans and to inspect those under pan cab mounts brackets. If replacement is needed you can align to the fixing points established on the frame. This will also establish where your new floor pans will be placed... bolt through the pan and under pan bracket then through the frame, cab shims installed and gapped per the overhaul spacing ( top of frame to bottom of new floor pan). Tighten bolts to meet that spacing. Your now cab is aligned. This does matter.. Don't ask me how I know this.
Some other tribal knowledge.
If you have to replace that bottom hinge pillar with a new patch panel first make a fixture out of 6" X 28" 16 ga steel sheet. You can get at a local fab shop, reasonably priced and sheared to size. After the outer cowl panel is removed, clamp the fixture plate to the hinge pillar and from the rear spot in the 6 hinge mounting bolts with a fine point sharpie or transfer punch. Remove plate, centerpunch then drill 6 holes to 3/8". Now you can cut out the bottom portion of the hinge pillar. Install lower inner hinge plate with swaged nuts to the new patch panel. Attach your fixture by the 3 bolts on the top hinge of your fixture to accurately locate the lower hinge pillar location by installing these 3 bolts. This fixture will ensure you bottom hinge is correctly placed on location. Having that bottom hinge out of location will cause issues when you install the door later on.
Before welding the outer cowl panel rebuild your door hinges. Do not buy aftermarket hinges. Strip the widow glass out of the door to make lighter, as you will be installing/removing these several times. Install door for good fitment prior to doing final welding /attaching of outer cowl panel. Go slow welding to minimize heat build up and warpage.
I am just finishing up my cab overhaul. Rear cab corners, floor pans. inner and outer cowl panels, underfloor cab mounts ,lower hinge pillar.
Hope this helps..
Good luck and enjoy!
