Hey Creep, not a stupid question at all, and if one doesn't know something,one only needs to ask.
From my understanding is Thames is the name given to the vans from Ford England, Popular is the basic model car eg., like the Standard '37 Ford compared to the Deluxe and the Anglia was the Deluxe model from Ford England.
On a lighter note,some rodders here in NZ don't regard English made cars as true hotrods even though it was you Americans that were the first to use them as drag cars etc..