what date did the last 1966 Ford Thunderbird convertible roll off the assembly line, day & month

thank you. The date code on the door plate reads ( 19 K ). Does that indicate the build date would have been ( October 19th 1965 ?

That sounds right; http://www.tpocr.com/fordbp6.html

Here are some Tbird links you may find useful. (I had a 66 once): http://www.tbird.org/DataPlate/vdata.htm , http://automotivemileposts.com/tbird1966interiortrim.html , http://www.tbirdregistry.com/see/vinb.htm , http://www.tbirdhq.com/ , http://www.fordfe.info/ExhaustInterchange.html , http://www.tpocr.com/fordvin6.html , If you need to replace VIN tags or data plates for anything post 1967, Marti Reports has that info: https://www.martiauto.com