Production Numbers
Total production of all models amounted to 440,032. Before
1970 when they changed the chassis numbering, you could tell
how many Imps of a particular type were made by finding the
latest example and look at the chassis number. Afterwards the
number stood for all Imps, no matter the type. So the number
on the youngest Imp shows the total number of Imps produced
since the change-over in 1970.