got a ticking coming from engine on my 4.2 supercharger V8 from the passenger side I've pinpointed it down to exhaust manifold gasket
has any one changed one before and is it a pig of a job to do
I am a bit mechanical minded so just wondered on time scale to do the job

If there were a v6, (probably similar) what you would do is:

Remove the heatshields in the wheel arch, (jack up, axel stands, remove wheel) but first mark them with numbers and take a photo in situ
and also make intersecting marks. They are a true jigsaw! Will save a lot of time later.

Purchase a long ratchet extension 24 inches or more.

undo the manifold bolts through the wheel arch.

you may need to undo the other end of exhaust from the cat too

when I jack it up do I put it full height so it don't throw a suspension fault when I'm done

and with out sounding totally stupid what should I take pictures of and mark

Access height is fine. You may need to lower the car part way to work under the hood.

Take pictures of silver foil heat shields

thanks for that kind sir I'll make sure pictures are taken