You'll need enough space for 2 disabled cars, plus laying out some of the extra parts for inspecting/cleaning (especially the manual trans and driveshafts).

Removal of both trannies can be done in the same day if you're comfortable w/ tools and have 1 or 2 people helping you. Also helps to read up and survey the parts to see where everything bolts/unbolts.

The manual trans install can be done in one day, but don't expect to be road-worthy right away. That's mostly to get everything bolted up and fluids topped off/bled. It'll probably take a bit more time to get it looking and driving right.

I'd definitely getting at least one helper, and a 2nd one to help remove the auto and install the tranny (just helps to have 2 people up near the bellhousing and one person to push from the back when it's ready.)

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1990 190e 2.6 - The only one I can really call "My Car".

1987 190e 2.3 - The donor car's up and running, only mods are Euros and a Sony headunit. My Dad's runabout now.

1990 300e 2.6 - The parents' ride.