I just pulled a transmission from a 123 and perhaps it is different and maybe you will need a few more inches but all I did was jack up the car about 18 inches, I used 4 heavy duty jack stands and I had plenty of room to pull the transmission and the differential and the axles and the drive shaft...I left the front of the drive shaft attached to the transmission...maybe you can recheck your calculations...and it is easier to pull the engine with the transmission attached if you can't get to the top bolts connecting the transmission to the engine...in that case you will need to completely remove the drive shaft.....but if you are just removing the transmission use your floor jack to let the transmission down and then pull the jack out from under the transmission...Jim

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James A. Harris