Bob, the Carter YF that came with my truck didn't have any numbers , either.
It was determined by carbking to be a mongrel re-man carb from the 70s or 80s or something. Base was from a 50s Willys Overland Jeep and the body was from from some 60s Jeep. It was jetted wrong, etc.
I ended up getting a correct YF carb for the 216 and rebuilding it with a correct kit.
I'll bet yours is a re-man assembled from random hodge podge parts and sold as an off-the-shelf Fitzall that offers mediocre performance to a variety of vehicles instead of perfect performance for your specific application.
