Triumph Repair: 1972 Gt-6 polarity, triumph spitfire, usa models

Question
In what year did Triumph Spitfire and Gt-6 changed to neg. ground in USA models. My 72 Gt-6 is what originally?

Answer
Hi Charles,
The GT-6 was negative ground. However, the British cars with generators can be changed to positive ground with a procedure. But I can't think of a reason to do that. The MGs came both ways in the generator models. Many owners of positive ground cars wanted negative ground so they could install late model radios etc. I changed many from positive ground to negative ground in the dealership. I have outlined the procedure in my "Tech Tips" page on my web site.
http://mg-tri-jag.net/tech1.htm

All cars with alternators must be negative ground. Many older British cars with generators were retrofitted with alternators which required a negative ground.
Howard