Miniature cabinet doors

I 3d print dollhouse miniatures and need to build cabinet doors. I found cabinet door designs but when i downloaded the OBJ file there are like 20 doors in 1 file that appear to be grouped as 1. I need help breaking the file into separate files for each door. I need to be able to scale them down to like 3 inches high by 1.5 inches wide and 1/8 inch thick.