85 300D "3/2 way vacuum" vs. "throttle microswitch"
 

I've seen a couple DIY articles on fixing the 3/2 way vacuum switches that are on the valve cover (actuated by a cam off the throttle linkage). This, supposedly will correct hard shifting (in addition to the vacuum dashpot?).
http://img.eautopartscatalog.com/live/D301312188MTC.JPG

On my 85, however, this is not present on the valve cover. Instead I have a throttle micro-switch which seems to be for "thrust cut-off".
http://img.eautopartscatalog.com/live/C701412167VMO.JPG

Is this part of an anti-slip feature? Does this serve the same function as the 3/2 way valve? Do I have a 3/2 way vacuum switch somewhere else? I am experiencing hard shifting intermittantly. I think it's probably the dashpot, but haven't checked yet...

That's a switch!
 

That is the kickdown switch -- it forces the transmichigan to downshift to the next lower gear, providing engine RPM will allow it. On the '85, it also operates a relay (the Klima relay) to temporarily disconnect the A/C compressor, making more engine power available for the neck-snapping acceleration that our diesels are known and loved for.