Good advice below... I'll try to simplify the way I go about it.

1) Put car securely on ramps or whatever so you can get under it enough to work. Make sure it cannot move, that is to say, one rear wheel and both fronts chocked good, handbrake set.

2) Under the hood.. remove accellerator linkage so it doesn't get bent when engine tilts back. Ditto upper radiator hose, or the radiator mount bolts so it can tilt back with the engine. Remove top two bell housing bolts now, as you won't easily be able to with the engine tipped back. They are easiest to get at from under the hood.

3) Inside the car.. put in neutral. That will allow you to rotate prop shaft, and also make easier the task of getting the shifter back in later.

4) Jack up one rear wheel, just so it can turn, again, allowing you to rotate prop shaft. I prefer to do so from the axle, keeping the suspension loaded.

5) Check and double check vehicle stability. It is at it's most precarious condition now. Remove prop shaft at rear of transmission. Prop it up against the top of the tunnel, as out of the way as possible.

6) Let that wheel back on the ground, chock it, set handbrake. Double check stability of car. Put jack under bell housing and put upward pressure. Now would also be a fine time to remove the speedo cable.

7) Remove four bolts that hold the crossmember to the chassis of the car. Unless the exhaust is in the way (shouldn't be in a 122), I just leave the crossmember attached to the transmission.

8) *SLOWLY* lower jack, allowing transmission and engine to tilt back. Be watching those heater hoses, brake light switch as said, and whatever else. Block it with a piece of wood between the head and firewall if it looks like damage is pending.

9) Unhook wiring atop transmission. The one to the 4th gear sender, and the reverse light. The wire between the 4th gear switch and solenoid can stay.

10) Remove clutch slave cylinder, tie it out of the way.

11) Remove the remaining bell housing bolts (including starter bolts), possible a dust cover at the bottom of the bell housing if you have one.

You should now be able to remove the transmission with overdrive and bell housing attached. It might be tight, might need to pry a bit. Shake, etc. As said, some folks like to separate the bellhousing. I don't. Not in a 122. Leaving the bell housing and tranny crossmember allows the unit to rest right side up, rather than tipping over and dumping oil all over your workspace.

At this age, it seems all cars are a little different. You might run into exhaust brackets that have been added.. etc.

Re-assembly would be exact opposite. A clutch alignment tool would sure be nice. it can be eyeballed, but not easily. Make sure the alignment tool slides all the way in and out easily after the clutch is tightened up. if it doesn't easily go in, the transmission won't either.

Torque specs.. Probably the flywheel would be one place where this would be a good idea. Clutch bolts too.

And man.. while I was in there, I'd sure want to do the clutch if its age is unknown. And maybe the transmission mount, while down there.

For the most part, it's pretty straight forward. First time I did the job, it took me a full week. Last time I did a clutch, it took less than two hours.

First and foremost, be safe!

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-Matt I ♥ my ♂