I thought about changing mine yesterday, as have all the gubbins off whilst changing turbo.
Remove engine noise covers, the big one and the little bit at back. 5mm Allen key, although I also had 1 10mm bolt?
Undo egr pipes (cooler input and the brassy looking recirculation one) brassy recirculation is a worm drive type with flanges on and the cooler has a spring type self clip, just pull the indent out and it clips back and just slides off front of egr. Remove vac line from egr.
At very rear of the inlet manifold, on right rear corner, there is a another bolt holding a couple of brackets on, take that 10mm bolt out. There is another 10mm bolt holding the dipstick bracket on right side, take that out.
Disconnect the fuel rail pressure sensor (or whatever it is) at the far back. You can see it and it comes off towards the right, push plastic retainer (on the side nearest you) away from to (towards back of car). Almost next to this, bit bit more to your right and bit lower to the ground, another sensor to Disconnect (push wire retainer in towards front of car and it comes off toward the ground, straight down easily).
Undo the 12 10mm bolts that are easily seen on the inlet pipes (they don't come out, they are clipped into the manifold). Watch for the 3rd bolt from rear, it has a clip for the engine cover that is loose when bolt undone and can be dropped etc.
Remove the 6 or 7 12mm nuts from the recesses of the intake manifold (5 down in each gap between seperate pipes, plus 1 in front of first inlet pipe finger and 1 at rear after last inlet finger). Be careful not to drop them if your sockets don't have any magnetism. The one on the back is near the brackets and sensors you've removed. I used a little mirror to find these rear bits, came in handy.
Remove intake manifold, watching the injector wires to the left.
Boom, your at the plugs:
Give them some extra pen lube and hope they don't break lol
Reverse in reverse. Make sure gasket surface areas are clean and fit new gaskets if you wish (it's recommended I believe) before replacing intake manifold. I'd give the egr a clean as well and intake manifold if needed (mine were stinking dirty and I got a 1/4 cup of soot coke and oily gunk out, yuk)
However I have no ideas about the torque values, trying to find them myself!
Edit, just saw this is 3 months old, but might help others in future.