I knew it was small - but gosh dang-it could you be the unluckiest with your refer MIA search!!!
This one is an M28 with a bottom shelf in perfect condition and 14 78" wide (measurement taken from inside door lip to inside lip (as marked on the photo) - not from inside tab to inside tab).
I thought maybe the 28 and 35 would be the same width just different hieghts like our 40 and 45 or 50 or whatever

. Can you double check the measurement so that we are infact taking the measurement from the same place?
.....and the saga continues of the missing bottom refer shelf.....
I have the M40 - with a perfect condition extra bottom shelf! measuring 16" wide and the 28 has a perfect bottom shelf - both the aqua with cross hairs...Can ya not just shuv it in and make it fit
Well I have one more chance to redeme myself and have my local girl checking with her vintage refer source for you. (He came through for our very uncommon size so maybe you will be 3X lucky???) I will offer that little 28 fridge for the effort and go and pick it up if he will make a trade for your shelf and rays shelf and freezer door on an M35.
And who thought this was easy tracking down Vintage parts