UPDATE FROM 2002!!!
Hi!
I haven't given up researching the history of my XK120 OTS!
With the help of John Elmgreen, Bob Stevenson, Bruce Carnachan, Alan G. Boring and many others I have collected more information of the early years of 670501 but the 1950-1968 gap is still open.
Can you help?

20.07.1950 Date of Manufacture, exterior colour: suede green, trim colour: suede green, hood colour: french grey
21.07.1950 Delivered to Max Hoffman Motor Co., New York
1950 - 1968 ???????
1968 (?) A "Lady Racer" sold 670501 in 1968 (?) to Alan G. Boring, President of "The Jaguar Affiliates Group Michigan",(34585 Quaker Valley Road, Farmington, MI.) acc. to Alan the car had a "fleshy" color thererfore the car was nicknamed "The Shrimp". The lady "ran the Florida beaches at Daytona for speed trials" (standard windscreen, spats, disc wheels). At time of transaction the lady was about mid/late 40s, resident of the Detroit area 1969 - 1971 Alan G. Boring
26.11.1972 Alan G. Boring sold the car to Steven Daniels (206E. Michigan Ave., Clinton, MI,
1973 Steven Daniels
1974 Steven Daniels sold the car to Michael A. Griffin (29154 Franklin Hills Drive - Apt. 109,
Southfield, MI) (as of 1973)
1975-1977Michael A. Griffin or Gordon Keller (PO Box 11, Mendocino, CA
1978 Gordon Keller sold 670501 to Ken Dalziel (UK) through Stephen Langton (UK)