Narrow 1980s openings
That gap matters. A house built in the late 1980s usually has a narrower single-car opening on one side and a double on the other, both running on builder-grade steel sections. A house built around 2002 is more likely to have come with a wider double-door opening from the start, sized for two full-size vehicles side by side, and an opener already wired for a heavier door.

