Good work Jimmy - that pesky outer tub boot was askew on my Kelvi too. It wasn't difficult to tear down I gather, they are pretty easy compared to other machines really.
Beginning in 1958'ish, Kelvinator & ABC machines were built with a slightly larger cabinet and a round "splash tub" for spinning the water into from the wash/spin tub.
This is a quote from a short history of Cudell, Ohio that gives some good dating info for appliance companies - the link to the entire article is below.
"White Sewing Machine Co. diversified in 1956 and bought small appliance companies, including Standard Sewing (1965), the Hupp Corp. (1967), the Kelvintor Appliance Div. of American Motors (1968), and the appliance division of Westinghouse (1975).
The company's name was changed to White Consolidated Industries in 1964, reflecting its holdings of machinery, tools, household appliances, and valves.
White Consoldiated purchased numerous other major appliance competitors during the 1970s, including Philco, the Ford appliance division in 1977 and Frigidaire from General Motors in 1979."
Gibson was a pioneer in the refrigeration industry, formed in 1877 and bought out by the Hupp Corp. in 1956 who later merged with White Consolidated in 1967. I have never seen any literature for laundry machines predating the WCI time so they would have been Beam/Franklin/WCI from that point on. (The Hupp Corp also owned the easy Easy brand name, formerly owned by the Murray Corp and was swallowed by WCI as well.)
There was some odd brand out-sourcing going on at Kelvinator around 1968 or so, after the sale of Kelvinator by AMC, some Kelvi branded laundry stuff from that era was made by Norge and not WCI... Very strange, muddled history!