My mechanic suggests a Cummings 12-Valve, as they are available for short money (his definition of short money and mine do not always align), parts/service should be available almost anywhere, and they are not overly computerized.
I agree that the photograph above does not align well with what we have. (I really like that transmission holder/stand that is in that photograph.) That would be considerably easier on the back than the method we employed, which was to lift it out from above.
Take Care,
Joshua L. Coder