You have the answer right there in the second and third pictures...It was a kit sold by Applied Technologies which stopped the fan via the grille-mounted "paddle switch" at speeds over 35 mph (not 100% sure) approximately. I know because I used to have one like that...worked good, but now kinda "old school". Oh yeah...it has nothing to do with a GNX, meaning that it's not a GNX-specific part. ATR sold the kit to be installed on any turbo-Buick...