Most the them use a 4 digit date code number on the back. The first 3 numerals are the day of the year and the last would be the year. For example, if you have 2489 on the back of the speedo it would have been made the 248th day of 1969. Post some photos if you want me to help you date code them.
Thank you so much C O D Y. This forum and its members are the best on Earth. Here are some pictures.
It's a Rallye dash cluster:
There is the code I was wondering about
So this particular speedometer fits the car! I don't have a fender tag and only had one extremely gone broadcast sheet. I decided two days ago to contact Galen Govier, just to get fender tag as correct as possible. This car is just a 383 -4 barrel vehicle and will never be worth a small fortune, but I've decided that one day my kids or wife might need to sell it. Having it documented is the best way to keep the value in my opinion and I was really worried that the Rallye cluster wasn't legitimate since this is an SE car, but I guess it is! You made my day C O D Y.
The cool thing is this car had everything there and lots of options when we got it, so there are date codes all over the place! I know some here don't care about tags, and provenance etc, and I don't blame ya for not, but after having so much worry wrapped up in her for so long, for me it makes me feel better.
And I really like the codes for some reason. They are fun, and hopefully Mr. Govier will find some record of the car out there. They are looking and I am praying!
So, doing the math, my dash was made 87 days before the year ended, which makes it fall right in line with an October build. Nice.