Although not as Wayne's tale above, there was an association between Studebaker and STP..
Our friends were a Stude dealer to the end (actually still operating today too) and years ago they showed me the original tiny jar of STP product sent to them by Studebaker Packard Corp. when SPC owned STP...late 50's/very early 60's I believe?.
Very C
L piece Rick!.
~ Pete