Thank you.
Yep - the text of ad is correct, I copied and pasted the title from my other gear listing and changed the date but forgot to change the ratio in the title - ad shows 3.73.
Here's that ad for the 1969 dated 3.31 ring & pinion:
https://www.yenko.net/forum/showthread.php?t=162452
Anyway, these truck gears are listed on eBay now:
https://www.ebay.com/itm/143673981517
Thanks again sYc Friends!
Anthony