Where do the door bumpers go?

[rynophiliac]

Where do the door bumpers go and how many of them are there on each door? My blazer only has 1 door bumper on each side right now right by where the door handle is in the door jamb. I see two more holes that look like they could be for more bumpers? One hole is on the bottom of the inner door (below the hinges) and the other hole is on the bottom near the corner of the door (on the latch side). Are these two holes for door bumpers also?