Spendy, but you can't beat the original Delco switches!
Part number 1993432.
https://www.ebay.com/itm/134408317128
Also, make sure the knob is tight to the shaft.
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1970 K/5 Blazer CST 4WD, Bronze, 93k ACT. miles, 350, 4 speed, positraction, 16.5" x 8.25" wheel option, tilt, tach, vacuum, AM/FM, manual throttle...Dad ordered and purchased new 4/70. Currently frame off restoration in progress...
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