Tachometer starts at the wrong end on idle?

I got a swap meet tach a while back and went to hook it up problem was it started at 8Krpm instead of 1K. I pulled the cover back and it was in 8 cyl position. green wire tach, red ignition, white light and black grounded.
Any ideas? its a cool looking tach and I'd like to use it.

 

you said Green wire tach, does this mean negative on coil ? because is where it should hook up

 

I put the green on the HEI "tach" position.

 

That is correct but what is it grounded to? Mine was doing the same thing until I put a direct ground to the frame.
Good luck.

 

it was grounded on the column. I made need to look elsewhere to ground it then.

 

That tach is for a reverse rotation engine.