Good Guess, Buddy
Andrew, I think this is probably a KDC-21 like the one I have in my garage and nearly made it to your kitchen.IIRC, models of this manufacturing date came without the china guard and adjustable racks. Could still be an "I" model but looks more like the "C".
Definitely a super cleaning machine for anyone who buys it, and also was WP influenced as evidenced by the above sump heating element which also means it has the plastic blower and used the loop element for water heating and drying.