After messing around a long time on trying to get the horn to work on the aftermarket 15” wheel on my 57 Chevy, I decided to try and track down an OE Belleville spring, and while searching, using the GM part number (17982401), stumbled onto the following site, While his specialty is 73-77 GM A-body & Monte specifically, he also has several parts locators to use in researching part #’s (so would need the GM #). Turns out there is a certain amount of cross application across years for some of the parts. The spring I bought has a different tension than the two repops I was trying to get to work (OE part is less resistive to movement), and made a good difference. I had a great experience with, ended up with the part I needed, and recommend them for your consideration.