This is a bit of body alignment that needs to be attended to at time of body assembly. The secret to getting good outer body panel alignment on the MGA is to start in the middle when building the body, and build the car around the doors. Adjust door post alignment first (if the posts are loose during restoration work). Then install the doors with hinges and latches and make the doors open, close and latch properly. Then install or repair body sill structure, and install rocker panels with reference to proper gap at bottom edge of the doors. Finally install the front and rear fenders with proper alignment to get the right gap at front and rear of the doors.

By this time the fenders will be for the most part fixed in their lateral location, and you would be moving the doors in or out a bit to be aligned flush with the fenders on the outside surfaces. One more concern here is where the door seal will mount on the spot welded body flanges, and the lateral space needed between these flanges and the inner side of the door for installation of the door seal. The original style furflex door seal with soft rubber flange needs about 3/8-inch space to fit properly. It might be squeezed down to 5/16-inch space (in places) for a very tight seal. Instructions from Clarke Spares and restorations for installing the door seal call for up to 1/2-inch gap between body flanges and inside of the metal door shell (before seal or inner door trim panel). It may also be common for the gap to be larger at the front than other places (tighter near the latch). It has been my experience that a lateral body gap of 1/2-inch will likely result in a loose seal with intrusion of road dust or a slight cool breeze in cold weather.

In reality, by the time you get this far you may not have much choice in width of the gap for the door seal. Position of the front and rear fenders may more or less dictate lateral position of the door for flush panels on the outside. If you're lucky you should end up with about 3/8 inch gap to accommodate the bulk of the door seal. If the gap is too small you might have to leave the door a bit loose with the outer skin protruding a bit beyond the fenders. If the gap is a bit too large the door seal may not seal properly. It is a primary function of a good door seal to accommodate a fairly wide range of body gap to compensate for a multitude of irregularities in panel alignment. To have more accurate control over this body gap you have to start much earlier in the assembly process, when the individual panels of the main body structure are being aligned before spot welding.

For more information on fit of the door seals see article INT-108C in the Interior Tech section.