Does anyone have a picture of how their roller tach is hooked up. I have a car that the previous owner often seemed to slop together, and I wanted to see if the way my tach is hooked up was correct. When I look at the backside of the tach from under the dash, there is one electrical connector that is not hooked up on the back of the tach. I would really appreciate anyones help on this one, because I would really like to see if this tach works.

HovsSS

I'm pretty good with a camera, but I don't see any way to get a pic of the back of the tack, with the dash in place. There should only be one wire to the tack, other than the light bulb. The tack wire plug is in the dash harness. The dash harness is hooked to the engine harness, thru the fuse block, then the tack wire goes to the coil. But the bottom line is, the tack wire should simply hook to the neg side of the coil.

Its a L shaped 2 prong connector. You could possibly use just 2 single straight or elbow ones if you don't have it. One is coming from the neg of the coil. I'm wanting to say the others the ground. i don't have my notes.I bench tested it before. Just with a meter on resistance,check from prong to gauge body on each to see which one is which. The same with cable at the ends just checked each one against the dash frame so knew which one is the ground. Next time i take it off was wanting to put the 2 lights in the gauge body on a connector so can unplug when taking off dash so can leave those in till later. Its a big pita for me to get up in there to plug and unplug those above the column. I'm up in bedford i can look at mine monday.

One of the plug is the ground. If yours is not plugged in just meter it to see which one is to the dash frame. If you don't get a reading possibly the connector is bad and he did some internal jury rigging to get it grounded inside. Really have to pull it out to see. I'd fire it up see if works.If does just fix it right someother day down the line when doing your restoration. There is a new gauge setup that goes in where the clock is. I like the roller the best especialy if you have the full gauge instead of lights. Great car,youll love it.

I can get you a pic of it if you need mine is out of the car while it's at the body shop

The top terminal gets a brown wire from the coil - post the bottom is a pink wire, +12 V form the INST fuse, power for the tach. Here's a pic (http://www.chevelles.com/showroom/data/500/68tach.jpg)

So its not a ground. I see your plate is even stamped. I interpeted it as a ground by using a meter from post to tach body. I don't really know how one works.