They're not all the same. There were differences even in the same series. For instance, a M cab key won't fit an M with no cab. Newer excavators and skid-steers use different keys than listed in the chart above. Old L keys don't fit newer L tractors. G series keys won't fit ALL G series but some will work in F series stuff. T series weren't all the same. ZG and Z100 series have several different keys ZD series keys are different too. I have keys to fit every single line from 1990 through current and I'm here to tell you, it's a big wad of keys. I think there's about 40 of them on the ring. The ring used to be hard to keep up with but as of the last few years not so much...there's so many keys on it that it's easy to spot from even a few hundred feet away. All Kubota, with the exception of one or two JD keys and a cat key.
I think the Japanese like to confuse us. "Stupid round eye!"
I think the Japanese like to confuse us. "Stupid round eye!"