About the dispenser...I was wondering when this would come up for discussion, but there were actually TWO versions of that dispenser. The original, from the late 60s was a bolt-on, that acted as an agitator cap and was not supposed to ever be removed (dumb design in my book). It was not long that this was revised however, I think by 1972 or so. The development of the small gold agitator cap, similar in size to the original black "thumbnail" cap, allowed the dispenser to be redesigned as a press-on dispenser, which was included in many 1972 and forward Kenmores with Straight-Vane and Roto-Swirl agitators. This same dispenser was adapted to fit the large capacity Penta-Vane and Penta-Swirl agitators via an extension which is bolted onto the top of those agitators and is of the same shape and dimension as the top of a Roto-Swirl, etc.
There are two ways to tell the two softener dispensers apart. The original has the metal threaded nut molded into the top, which you can see in Andy's pic. The later removable dispenser has plastic threads that are part of the mold, which screw into the base of the dispenser. These were meant to make the machine more accessible, make the dispenser easier to clean and to remove from the machine altogether if the user so desired. Ours was only in the machine when needed, which was sporadic as we used dryer sheets a lot.
Secondly, if you compare the two dispensers side by side, the cone-shaped diverter in the exact middle of the dispenser rises to a narrower point on the fixed version than on the removeable one. My mother's 1974 Kenmore had the removeable dispenser and one of my friend's moms had a 1971 or so Kenmore 800 with a fixed dispenser, and I noticed as a kid how they differed. I tried to remove their dispenser to show his mom how to clean it, thinking it was like ours, and was thoroughly frustrated and embarrased that I clearly didn't know what I was talking about when I tried in vain to get it out of her machine! (I took my Kenmore knowledge seriously, even back then. LOL!)
If I had a fixed version of the dispenser here, I'd take some photos for comparison, but I don't believe I ever saved one.
Gordon