Hi Bill

Your comments about glass start a whole new topic.
I know veteran cars used window glass, and thought the Seven driver may have encountered!
My RP has side glass labelled TRIPLEX toughened, I suspect the triplex part is just a Trade name. Most cars with true triplex laminated glass went yellow but whilst Ford V8s in this state were common I cannot recall Sevens.

I have not broken any to find out.

Curious what you reckon was used and when?

Location: Auckland, NZ

I'm pretty sure safety glass became standard for windscreens in late 1928/early 1929, and all round in mid-1930.

Hi Bob, if you look closely at the word 'toughened' on triplex glass you will see a dot under one of the nine letters of the word. No dot is the end of each decade, a dot under 'u' the third letter in would mean the glass was made in 1933 for your box Saloon.
This code was used by Triplex up until quite recent times. You should be able to date a car by its glass as they should always have all the glass with the same code providing none has been replaced.
Just a bit of useless information. Ian M

Location: Bristol