I would almost bet money that this is the source of the counters.
http://www.lafayetteevaluation.com/default.asp

The rest of what I see in the photo looks like something made by a
rallyist! The counters would just advance a click each time there is
an electrical impulse applied. The rest of what is there is probably
just a switch (to generate the impulses) operated by a cam that is
driven by some gear ratio off of the speedometer cable.

I built a variety of such setups many years ago using a hall effect
switch mounted on the wheel. Everything was non-mechanical and
sealed in epoxy. The only real problem was a sealed bearing but they
were relatively cheap. A minimal amount of electronics and you had
a factorable odometer.

SD



--- In historicrally@yahoogroups.com, "steven Silverstein"
<milano164@...> wrote:
>
> All very good information. I hadn't seen any Lafayette instruments
> either which had prompted the question. The system looks well
built
> and thought out.
>
> I keep wondering if there is a way to utilize this system again.
>
> IF by chance somebody has some ideas please feel free to write me
> directly.
>
> On the other-hand Maybe it would be best just to leave it alone...
just
> as a novelty of the period.
>
> Best Regards,
>
>
> Steven Silverstein
>