I've got an FTO GR, and new set of spark plugs to go on it. I need to get the exhaust manifold off to get to the back 3 out, and it looks like that'll help with the front 3 too, but it looks like a right **** of a job to do! Anyone got any instructions, diagrams, etc. to help me out? Kind of urgent too!!

Only a month too late but just in case,

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i got this done on mine a few weeks back.
you ony need to change the back 3 plugs every 60000 miles.
but if you still need to do this be brave it not that bad.
take of air box and pipe's . then you can get to bolts at back of manifold.
undo all bolt in an anticlockwize one at time and lift up there are two pipes conected to it make sure you put them back on when finished but plugs in.
look harder than is.but when you put manifold on. do the bolt up abit in turn.
to get a good seal on gaskit. good luck