Let's see... I did a 1981 into a 1980 Just last December.

Definitely do not let the two piece driveshaft separate before you get to paint
marks on them both so they align back exactly the way they are in the cars.
Do it for both, you never know when you will need the spare.

You can paint the marks while you are under there disconnecting the trans
from the driveshaft flexplate. - Which is the propeller shaft at transmission you asked about.

Definitely lift out the trans and engine still bolted together.
I strongly recommend a load balancer for shifting the weight and angle easily.
(Harbor Freight $21 when on sale).

I lifted the rear of car to make the angle at the front end easier.

Do think about those motor mounts while in there. Check for the heat shields on the motor mounts (one of my cars was missing them).

Good luck !

__________________
80 300D 340K Owned 30 yrs
83 300SD 440K Owned 9 yrs - Daily Driver 150mi/day
02 Z71 Suburban 117,000
15 Toyota Prius 2600 miles
00 Harley Sportster 24k
09 Yamaha R6
03 Ninja 250