Did mine at the weekend (2.4 JTD 10V), having done the cambelt, so still fresh in my mind.
Biggest ballache was the front lower engine mount bolt was seized. Ended up having to unbolt the mount and engine bracket as one assembly. And then discovered that the bolts that hold the mount to the chassis leg were also partially seized, but luckily there was an access hole in the side of the chassis leg where I could dump a can of penetrating fluid through onto the bolts
Anyway here goes:
Remove the engine cover and top "dumbell" engine mount bar (17mm bolt at either end).
To make access easier remove the engine mount bracket that this was bolted to - 2 17mm bolts and one big (M12 if I remember right) ribe bolt.
To remove the belt, slacken the bolt 15mm bolt on the eccentric adjuster pulley, just to the right of the crank pulley as you look at it through the wheel arch, then fiddle the belt off and out. It may help to remove tension by using a 32mm spanner on the spring loaded tensioner and turning anti-clockwise.
Remove the crank pulley (just the 6 M8 ribe head bolts not the big bolt in the centre).
Remove the top fixed idler pulley (13mm bolt).
Now you have to drop the engine on that side. Trolley jack and big piece of wood under the sump. In theory undo the 19mm bolt that joins the lower engine bracket to the mount. Mine was seized (see above) so had to remove the mount and bracket as one assembly.
Lower the engine to get access to the centre 8mm allen key bolt on the totally over-engineered spring loaded tensioner. Undo this then the 3 13mm bolts on the lower part of the tensioner, and remove this tensioner.
Remove the 15mm bolt on the eccentric tensioner and remove this tensioner (this is why you have to drop the engine as otherwise you can't withdraw the bolt as the engine mount is in the way).
Replace the top fixed idler pulley first, then replace the eccentric adjuster pulley but don't fully tighten.
Then offer up the spring loaded tensioner so that the three lower bolts line up (takes a bit of jiggling).
Put the three lower bolts in and tighten.
Then get a 32mm spanner on this tensioner and swing it clockwise a touch so that the central allen head bolt lines up with the hole in the engine block and wind the bolt in but don't completely tighten.
Now with your 32mm spanner turn the tensioner anti-clockwise against spring pressure until the hole in the tensioner body just above the pulley lines up with the matching whole in the engine block. Then insert something through the holes to hold the tensioner in that position. I had an small, old allen key that fitted perfectly.
Refit the crank pulley and tighten the 6 ribe bolts.
Now refit the belt around everything.
You then have to tension the eccentric tensioner. I found that a sturdy pair of right angle long nose pliers fitted in the two holes in the centre of the tensioner, and allowed me to turn it clockwise (so that it swings towards the crank pulley).
You need to tension it sufficiently here, to the point that allen key or whatever that you inserted in the spring tensioner can be withdrawn without resorting to violence ie. you have tensioned the belt such that the belt is holding the spring tensioner in position.
Tighten the central bolt on the eccentric tensioner, then the 8mm allen bolt in the spring tensioner.
Raise the engine back up and refit the lower engine mount bolt.
Refit the top engine mount bracket and the dumbell engine mount, then the engine cover.