I don't know anything about these tachs, but I'll give you what my parts books show.

3171216 is listed as the head assembly for '61-'62 series 10 thru 30 (no distinction between 6- or 8-cylinder). The numbers are 3852111 for '64-'66 series 10 thru 30 6-cyl, or 3839947 for '63-'66 series 10 thru 30 8-cyl. units. A transmitter is only listed for the '61-'62 8-cyl. units.


Curt
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1953 Chevy 6400, 1957 Chevy 2dr Sedan
--"Mediocrity is easy, the good things take time"