The .961 has a proper boost actuated wastegate, the .962 has an ECU/vacuum actuated wastegate. My guess is the .961 uses vertical injectors and prechambers where the .962 uses angled injectors and prechambers.

I imagine there are no relevant internal differences if you're thinking about a swap. I mean compression, cam lift and duration and such things might be different, but so what? I would be more concerned with oil cooler fitting locations, sensor locations, using the appropriate mount arms, etc. Nothing having access to parts off both cars won't solve.

The tendency to snap chains seems to be a .962 thing. Maybe there are too few 190Dt's that there isn't enough noise made about snapping chains. I haven't heard of even one.

Sixto
87 300D