I am glad you said something about the non-existent 2000 Aurora.
'95 was the first year for Auroras. The '95 had a higher flow oil pump. And they also had crappy brakes and suspension. '95-'97s also have an oil cooler and bigger radiator that they dropped in early '97. '97 came out with better suspension which is unique to the '97 year. '98-'99 had the superior suspension of the Auroras.
I think '99 would be the year to go with if you were interested in a Classic Aurora. Putting an oil cooler and bigger radiator in a '99 would be the ideal setup. Keep in mind these are just some mechanical things, there were also a lot on other changes of options through the years.
2nd gens are a whole different story, I don't know that much about them, but I love them all!!