I realize that you are talking Shelby prices rather then Cobra prices and they are two different animals BUT I go back further then most here do these days.
I remember the $5,000 289's and $8,000 427's.
When CSX 3121 sold for $23,000, everyone went WOW, unbelievable. Now we are talking around a million.
What's a $5,000 R Model sell for now?
The point is, the trend is up, not down.
How high is up? Who knows but don't expect prices to crash anytime soon.