Water pump is about 6 hours start to finish.
You will have to work to get the rad full --squeeze the upper radiator hose, then use a pair of plier to clamp the overflow tank line shut and let the upper hose go. This will suck coolant down into the lower end. Repeat until only water goes through the overflow line when you squeeze the radiator hose.
If you just fill it til it won't take coolant by gravity, it will seriously overheat, I know, I nearly cooked the TE!
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!