This is just a little input on the fender issue, years ago I made repro fenders for 32 Fords so I'm not shooting from the hip. Even thought these were fit to an original frame when they were shipped I had some people with issues.
From my experience I found that the fenders were best test fitted by positioning the fender front to back, meaning the fender was placed upon the frame rail and the front mounting screws were used as alignment pins. As the fender alignment moved to the running board mounting position, the fender aligns height wise to the height of the diamond pattern on the board, not to the top of the edge bead rubber. This leaves a 1/4" pie shape gap for about 2" at the junction of the running board, fender and frame rail. This gap is correct for 32 Fords, If you attempt to tighten it up the fender doesn't fit correctly.
The majority of issues revolved around that transition inward curve of the frame from the front body mount area to the front of the vehicle. It seemed that every repro frame maker had a different radius of curvature and that varied side to side. Didn't make a difference if it was a stamped rail or a welded rail frame. In most cases the positioning of the rear tab that mounts the hood hook and fender to the frame was the point of contention. In may cases the spot weld had to be cut and the tab repositioned to tighten the fender to the rail. In some cases the frames curve were too square and this did not allow the fender curvature to match the frame either. Now I think the tabs are not even installed on fenders and the customer must match their frame.
I also encountered problems when the center cross member had been replaced and the frame was slightly bowed outward, this kicked the fender away from the rail and the running board and made a tight fit difficult and if the front cross member was replaced and the frame pinched in slightly at the front.
I think that it is very difficult to cast stones at the products on the market with out a full evaluation of each fit issue as an individual case not even taking into consideration that the nice gennie frame may have been involved in collision 60 yrs ago, long ago repaired and difficult to note the damage.
Anyway this is just a little input into the fender fit topic.