Neat Rig if I were younger it would be in the garage. Paul take note 50 Buick Roof Lights again. To those interested the engine not running should not be an issue they were bulletproof. Just the usual pull valve covers and free up valves before cranking or have bent pushrods.
Plexiglass can be polished to being crystal clear again, if you have the patience and tools to do it correctly. They were originally flat plastic that was heated over a wooden buck to get the proper curvature, and then trimmed to the proper size. I learned how this was done from Jack Pinner, who was there when his father was doing this. Today, if you have access to an oven, it shouldn't be very difficult to make a replacement once you have the wooden buck fashioned.
Knowing what it costs to redo an interior, I would guess that it could easily cost $8,000 to restore the interior of this vehicle, and add an additional $1500 - $2000 to re-chrome the bumpers. Paint is another very expensive part of a restoration, so when you are done, I would figure about $25,000 in restoration costs, plus the purchase price. It will be a one of a kind car beautiful car when done.
I doubt it started as a Le Sabre if my memory is working the big motor was not available in the Le Sabre. That was the gimmick used to sell the Invicta. Perhaps it could have been special ordered not sure on that.