'66 Sure Grip ID?

'65 S said
The '65 Barracuda S I inherited came with lots of parts and pictures. Sometime in the early 80's my uncle bought a wrecked '66 Formula S and striped it for parts, engine, 4 speed, and the rear end among other items. If I've read correctly the '66 came with the small sure grip? Is there anyway to ID it from the outside or does it need to be opened for that? I assume that the little tag isn't enough to go by because I see they're still available new and could be added to any rear.

This is what came with the car, and also a poor shot I took today of the rear in the car. I don't know if he switched them or not?

ThanksView attachment 1715437047 View attachment 1715437048

I could be talking out of my tailpipe but the tag on the rear in the first picture could be calling out special gear lube as they do sometimes in locking units. You could remove the cover and look at the carrier and take some pictures and post them and get a better opinion.