Don't know about a V8 but I expect similar, I did a 300Tdi box out and clutch replacement on the floor of my garage, not even a trolley jack, no rear crank seal replaced, all up about 7 to 8 hours and I'm not ot a young bloke or a strong bloke, but I made up a lifting gantry affair that sat on the front foor and supported the gearbox through the transmission tunnel/gearstick opening.
Just remembered also I had two broken off bell housing bolts to remove while the gearbox was out,
Not something I would choose to do as a regular job, but doable.