The failure of original latches is due to worn hinge pins from lack of lubrication. This leads to gradual, un-noticed door sag over time and many opening and closing events. This sag causes misalignment of latch and striker, causing damage to both until the latch becomes too deformed to function. This damage can be corrected by straightening bent parts and welding worn metal back on. A right door latch makes a good pattern to work with to determine what metal needs work, since it normally is in much better shape from less usage.
Carl

1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission