Just the question I was about to ask!
My Norwood 68 coupe model build - 12c
Seat belts read
Irving 1968
Model # 237
49 A 67
They have the black plastic covers.
The different model numbers are interesting - 137 and 237. Any clues as to what that means?
There's also some belts on ebay the same as mine but with 1968 #330 1H28 68 & 1H24 68 on them
Would that be the 24th and 28th August 1968?
Did they change the date coding system at some point?
btw Dave, your ssnake-oyl link is broken with a comma. Their seatbelts look great, very detailed! but I couldn't find info regarding decoding.