Ok, So i have a 1990 Dakota 3.9L and i was wondering how wouldi go about adding a after market Tach to my truck, were would i connect everything?

thanks

 

I just put one in last week. On mine, I used the ashtray light wire to hook in the light (white wire) for the tach. I put the ground (black wire) on the same ground bolt the radio uses. For the power wire (red), I used a spade lug and shoved in an open slotin the fuse panel (use a voltmeter and find one where power is only on with the key in the ON position - since I don't have power windows, I used that slot). I put the signal source wire (green) on the negative side of the coil.

 

ya, I put one in mine acouple years ago. its on the top left of the dash. I ran mine to a toggle switch. so I can have it one when I want to. and I'm obsessed with switches