So, I just checked the one in my '70 and the looks and measurement are the same as yours. The one in my car is the original from my car as far as I know. I've owned the car since 1983 and I've never changed it and there's no indication that anyone else changed it or even messed around with the dash before I got the car.
I didn't know that you needed the measurements for placement you'll have to give me a few more days on that, I have to move some things around again to get back in the car. One caveat on the placement, I did have the wood grain on the dash restored by Instrument Specialties. I'm assuming, but confident, that they measured the placement prior to removing it from the dash and that they put it back in the factory location, it looks correct to me.