Reaper saw your add abt the 3 inch tach buick i have 1 in my car it lights up but does not move i had a key made for it today that didnt help needle goes backward when i turn it poped the hood i see a green wire but have no idea where to plug it into the dash stock tach works but this one dosent just wondered if you had a clue where that 1 green wire sitting under the hood goes to make this work thanks Ted