I'm not sure what that lister's definition of "old school" is but that Caddy ain't old school by a long shot!!
I spent my early 30 or so working years operating a body shop up North and I specialized in old classic and muscle car restorations mostly from the late 60's through the early 80's and you probably would drool all over yourself if you saw some of the vehicles that were brought to my shop and how they looked when they left!!
My favorites were the GTO's and early 442's. I agree that GM had the ticket on "old school" machines but MoPar had some classy rides also. And you can't fault a properly built up and maxed out Hemi engine either!! And, not to slight Ford, they
did have the Shelby Mustang but most of the other models were not in the muscle car class of those already mentioned in my opinion.
Good luck in your search take your time. There are still old rebuilders sitting out there in somebody's garage, barn, or back yard. Ya just gotta get out there and search them out. Some of my best finds were on road trips fishing down in the backwoods foothills of Southern MO.