Hi All
If I buy a "Tnk Regt HQ Sqn", formation 139 in Nov 1941 the formatiom seems to have unit 066? "Tetrarch" tank as an option. As far as I can make out these tanks only saw service in madagascar in the early war years and never formed part of formation 139 in 1941 or possibly at all.
see
http://en.wikipedia.org/wiki/Tetrarch_tank for instance.