the first optional turbo was added to the 7.3l idi in 1993.the last "full" year of the idi life cycle before changing over to the di.
'94 offered the optional turbo add on for the idi as well,after that mid year of '94 we call it to avoid confusion with the introduction of the di (psd) of course turbo's were standard equipment for diesel engines offered in the ford trucks.

 

Yess I knew they changed to PSDs sometime in 94. And thanks all for the encouragment. I'll be changing my albums and all that with new pics of this truck. It is amazingly clean inside. In my opinion.