I am not actually an authority but my wife and I have had two diesel cars, a diesel truck and a diesel tractor. And I know some of the history behind the 350 Oldsmobile Diesel. As you may be aware, although the engine did use the same accessories and could be bolted into the same spot as an ordinary 350, it was not actually a conversion but a new design and a completely new block even in the beginning. It did use many of the same parts as the gasoline, most notoriously, the same number and type of head bolts... which were not suitable for an engine with a 22.5 to 1 compression ratio.
My dad and I were very excited about them when they first came out in 1978. The first batch was SO BAD that it did great damage to GM’s reputation! In 1981 they came out with a new variant with numerous modifications and improvements that solved nearly all of the issues. By that time there were so many horror stories that the public soured on diesels in cars made in Detroit and diesel vehicles in general. It probably did do more damage to GM's reputation than the "step down V-8".
There is a short and interesting article here:
http://www.dieselhub.com/idi/olds-diesel.html
I appreciate the information.
My recollection, which is obviously not as good as yours, (The downside of being an old geezer), was that the Engine was just a slapped together off the shelf fix to get GM into the Diesel Market Segment.
One think I’m sure of, if anyone needs any information about any subject, there will always be another FReeper that knows the answer. Take Care my FRiend.