Pump, injector lines, throttle cables, brackets, throttle pedal, DB2 mechanical cruise control if you intend to keep it, bunch of little PITA bits I'm probably forgetting.

Then, if an auto transmission: wiring harness and TCM from a 93. Or you can spend 500+ bucks on a stand alone system. You can skip that if it's the truck in your stats as you're a standard.

Best advice?

Just replace the DS4 with a rebuilt....

 

most DS4 issues are just the stupid optical sensor...

had a friends who died due to that sensor going bad, but on reccomendation of a shop he replaced the whole pump and PCM

 

There's a familiar story.

The 6.5 TD is just a misunderstood old beast.

It's not complicated, but most techs just don't know how to troubleshoot them and could care less if they ever found out.

Just not enough money to be made out of 'em.

Thing is, with an optical sensor change it's supposed to be run on a test stand in order to set it back to specs. So the GM/Stanadyne troubleshooting usually just defaults to "change injector pump".....