Understanding the Commission Number prefix that was added when cars were assembled outside the UK
When cars were assembled outside the UK (Usually for tax purposes), Triumph added a character in front of the normal alphabetical prefix of the commission number.  Initially, this was an alphabetical prefix  of "B" for Belgium but was changed to a numeric value of "1" as other sites were brought on line.
Place of assembly

Belgium

Australia

New Zealand

South Africa

Malta

India

Eire (Republic of Ireland)

Phillipines

Peru

Portugal

Israel

Identification Prefix

B changing later to 1

2

3

4

5

6

7

8

9

10

11