I mentioned this before, do a search.
Anyways, here it goes...
I slipped a new one, without removing the water pump. NO tool needed. The secret is to use the MB hose (less than $10), since the OE aftermarket is too stiff.
The procedure is as follow:
1. Release the clamps and remove/cut the old hose.
2. Use a lot of vaseline or grease and cover completely the new hose with it.
3. Push, pull, cry, swear and then stick the small end first in the small opening between the cylinder head and the thermostat housing. The big end will just follow.
4. Use new clamps and then you are done.