Chuck,
That's a very nice original.
I am one of those who just can't warm totally to a 4 door.
Always wanted Dad to get a two door, and he never did, so on my own, I have never bought a 4 door, and probably will never own a new Buick again.
But, I did want to comment on your 73, Dad had a 72, and when you consider that is a WI car, it is flat out AMAZING to be in that condition.
Good luck on your auction
Dale