Triumph Repair: Spitfire 1500 Trip Odometer Reset, Spitfire, speedometer

Question
Just acquired a 1978 Spitfire 1500 in close to original condition. Very drivable, which I'm doing now. But I've looked everywhere on the car and also a Haynes manual and all over the Internet, and I cannot find the reset button, knob, or whatever it is, for the trip odometer on the stock Smiths speedometer in the dash.

The shop manuals are great for blowapart diagrams but it's not clear what I should be looking for. Naturally, I've groped all over the dashboard and far enough underneath where it couldn't possibly be. There's something with a hex nut on it on the bottom side which is about the closest to where I would expect to find it but it doesn't turn or push by hand. I haven't yet stood on my head to take a direct look underneath.

Obviously, this isn't stopping me from driving but it's annoying. I was hoping I was just missing something obvious.

Thanks for your help.

Answer
Kevin,

The Spitfire has a trip odometer reset that is a black plastic twist knob with a black plastic cable housing running to the back of the speedometer.   It normally was on a bracket attached to the bottom of the dash over near the ignition key.   

The "something with a hex nut on it" sounds about right.  You might try a small mirror and a flashlight to see if that's what you're looking at.


Cheers,

Jim