Not my favorite color... but looks rare https://www.hemmings.com/classifieds/dealer/buick/century/1801992.html
It'd be a neat car; if you can get over that colour. Very classical "Malaise Era",...priced well to reflect that.
Rare?! Yeah, I think it's a "one of none". Weren't '73 - '75 (Century) GSs the std./fastback roof line? Not the formal roof line like this car. Add some decals and a hood tach and .... viola!
Just checked the sales pamphlets, yeah, "Franken-Buick" all the way. Still, it got a lot of us talking, imagine what it would do at a car show. Ensure that buckets are strategically placed all around the car, that way you don't have much of a mess to clean up.