I'm currently in the process of gathering parts and information for an om617 swap into my AMC Eagle and was wondering which car would be best to look for to get the right engine. Forgive any ignorance on my part about diesels or mercs as I'm not too familiar with both other than a broad understanding of the diesel cycle.

Basically, what car had the best engine in terms of reliability and potential.

These engines are completely mechanical as well, correct?

Any information will be greatly appreciated.