On many QuadraJets there are 2 secondary throttle shaft return springs; an inner and an outer. I believe there are 3 versions of the outer spring. I've included a picture. I don't believe they are interchangeable as they fit specific shafts for different QuadraJets. From the picture, can anyone tell me which spring goes to Chevy, Olds, Pontiac Buick and Cadillac?