Triumph Repair: Triumph Spitfire Overdrive, triumph spitfire 1500, speed gearbox

Question
I have a 1979 Triumph Spitfire 1500.  The wife gave it to me as a surprise (to keep me busy) when I returned from Iraq.  I had one in college a looong time ago.  Question - Do I have OVER DRIVE, if so, how do I find it in the gear shift pattern?  Sorry for the stupididy of this question, but I cannot find it if I have it at all.

It runs great, but needs love like they all do.

Answer
Tim,

Congrats on the Triumph friendly spouse!  

As to overdrive.... on the Spitfire it's an electrically operated unit that "replaced" the tail shaft on 4 speed gearbox.

On the 1979 model the control switch should be on top of the transmission shift lever.  Sometimes when people fit one to a car that doesn't have o/d they wire in a separate switch as most vendors have a bad habit of not providing the proper shift lever (different from the stock 4 speed).

Otherwise you can crawl under the car (after supporting it safely) and see if there's a "lump" on the back end of the transmission.  


Cheers,

Jim