There should be a vertical seam part way along the lower sill (rocker panel) just below the door. If it isn't there this suggests that the car has had it's sills replaced or smoothed over with body filler.
This factory parts diagram shows where the seam should be.
On my car the rocker panel is in 3 pieces . The center piece overlaps the front and rear piece Is that seam filled in smooth as it was before I stripped it? Taking pictures would be greatly appreciated. Thanks