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[Mr79C10]

Hope this is the right place for this post. I didnt see a "Electrical" section.
 
My question is Im going to be replacing my fuel guage with a tach, so Ill be installing a smaller fuel guage like

  So trying to find out what Ohms I will be needing.
My ride is a 1979 C-10 250 L6 2wd

Thanks for any and all help.

[VileZambonie]

0-90 ohms is stock