Guage?

[onebadsierra]

Ive got a 1990 gmc sierra. I am currently in the process of trying to design how i want my guages to be in the dash. I am looking at running the autometer carbon fiber guages with a 3 3/8" tach and speedo, and 2 1/16" voltometer, water temp, oil pressure, and fuel guage. What i am wondering is, do i need the mechanical speedometer or do i need to get a electronic. It is a 90 gmc sierra, with the 700r4 tranny. I wasnt sure about this, so any comments would be greatly appreciated.

[1 Clean 91']

You'll need the electronic one.

[1badgmc]

:word:

[onebadsierra]

You'll need the electronic one.

I was thinking the same thing, but i wasnt sure. Also how do the carbon fiber guages light up at night?