Outstanding identification Diego, these two models are so close it’s difficult to say with what’s shown by the OP photo.

I see you tagged the Olds into the photo but comparing the two, the only difference I can tell is a body line detail that’s below the drip rail, the feature is tangent to the curvature of the rear glass upper edge and connects to the tangent of the door glass upper edge. This feature appears only on the Olds and missing from the LaSalle, for this reason I’m of the belief the OP pic is a LaSalle