If the water level as only gone down by less than a cup there may be no problem it could be just the coolant pushing round the system and finding it's level, in the manual it says keep an eye on the coolant level once you've refilled and run the engine then top up if needed.
Top up the coolant and see if it goes down again, have you driven the freelander or as the engine been running while stationery.
You also said it sounds louder this could be because it takes a while for the oil to get pumped back upto the hydraulic tappets, did you change the oil and filter, coolant could be in the oil from the original failed hg and when you removed the head.
Top up the coolant and see if it goes down again, have you driven the freelander or as the engine been running while stationery.
You also said it sounds louder this could be because it takes a while for the oil to get pumped back upto the hydraulic tappets, did you change the oil and filter, coolant could be in the oil from the original failed hg and when you removed the head.