Nice site.
As a kid, I was driven around in a couple of then-new 1980 ninety-eights, one of them a diesel.
I recall the diesel owner tried to convince himself the extra cost of the diesel was worthwhile, even though the car was so slow it was IMO not particularly safe to drive.
But I was impressed with the comfort and silence of the cars.
Personally, I built an '81 Fleetwood with a warmed-over Olds 455.