A lot of things going on at the water pump:

- water pump attachment to thermostat housing (not the turret)
- thermostat housing attachment to block
- radiator fitting (turret) attachment to thermostat housing
- radiator hose attachment to radiator fitting
- transmission temp sensor (603.96)
- cabin heater core return line to thermostat housing

And for some reason, the water pump pulley is a b!tch to remove.

Good luck

Sixto
87 300D