yes i would fix it. it isn't hard and then if you get caught out in the rain you dont need to worry about your carpet getting wet and causing it to rust worse.
This 87 car sat in a field for years before you found it. Another year or so and it probably would have been towed off to the crusher. I have a mint floorpan for it and when my welder gets finished you will not be able to tell the work was ever done.
