Another alternative is to locate nice used originals, or even NOS. Problem with NOS horns is that even with the proper part number, GM supplied a correct horn body, but the mounting brackets supplied in the box were somewhat universal, and were attached by a large single nut onto a spot welded threaded boss. These horns can be used if you carefully drill the spot welds holding the bracket to the old horn, then drill the spot welds holding the threaded boss on the NOS horn, and finally weld the old bracket to the NOS horn. I just did this for my 1970 Blazer. I could not find any good used high note horns, but an NOS high note appeared.
Part numbers for your reference:
High note 9000011
Low note 9000235
https://www.ebay.com/itm/Chevrolet-G...MAAOSwjxRgKzX0
https://www.ebay.com/itm/GM-HORN-LO-...sAAOSwzO1gVkiF
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1970 K/5 Blazer CST 4WD,
TOTM winner December 2024! Medium Bronze poly, 93k ACT. miles, 350, 4 speed, rear positraction, 16.5" x 8.25" HD Kelsey Hayes wheel option, tilt, tach, vacuum, AM/FM, manual throttle...Dad ordered and purchased new 4/70. Currently frame off restoration finally getting close to completion..
1970 K20, To be a clone of my Grandfather's K20, Dark Blue poly, 350, 4 speed, 16.5" X 8.25" Kelsey Hayes wheel option, tilt, tach, vacuum, AM radio. Latest project truck
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