Fabulous! My folks had a set of WCI-64's with that combination of pulsator/detergent column. The little hard plastic cap could always be found in the box of "Fluffy All".I would not have recognized their machine with the cap on the agitator! I think many other folks also considered the cap as nothing more than a measuring cup------and many ended up lost that way too.
With the larger tub, these three-ring agitators did not tend to tangle quite like the ones with the smaller tub (pre-'62).Of course, one still had to observe the "rule" of loading the clothes by dividing the tub into "quarters". I guess with the extra room the clothes did not roll over quite as fast.
Our set lasted and lasted, finally finnishing out their days, in "commercial" service at the funeral home, sheets and towels galore!
I know you will enjoy this fantastic and rare set.
Congratulations!