Here's a side by side comparison of the faces; the image of Lorraine is from a TLI slide scan. In this pic I'd say one of the images is flipped so the faces are mirrored. The features of her smile to be considered are the overall shape, the lines at the sides, and dimples. Now have a good look at her nose. The nostrils are fully visible even from straight on and the sides recess upwards and outwards as we look back towards her face. For me these features are an exact match and I don't see how these faces could be so identical and still belong to different women. My opinion is Marsha = Lorraine.
In the TLI images her breasts look a bit fuller and for me she looks to be a bit older overall. But we have very little of Marsha to go by so I still think they are the same.