After the interior of the car was nearing completion I hung the doors and installed the trunk lid so the gaps could be adjusted as close to 3/16 of an inch as possible. I started by adjusting the gap at the rear of the door along the quarter panel and also the bottom of the door and the rocker panel. Since both the rocker and quarter panel are fixed and can't be moved I would move the hinges and align those gaps as close to desired as possible. Once I got those gaps where I wanted then I adjusted the front fender in order to get the front of the door gap looking good. At this point the gaps are close but by no means close to acceptable.
Where the gaps were still to wide (over 3/16") I would cut off a piece of 1/8" weldable rod that was long enough to span the distance of gap that was over the 3/16" measurement. I would then weld that rod onto the edge of the door and then grind the door edge to the correct gap.
Where the gaps were to narrow I would use a thin cutting wheel and make a slice along the face edge of the door parallel to the gap that was too narrow and then hammer the door skin to close the gap and weld it shut. Doing that process would open the door gap by the width of the cut you made with the cutting wheel.