im doing the same job right now.
theres a few bits to take off, its got near to no access (im working on the floor, no ramp). ive wrecked my manifold heatsheilds because the bolts were rusty, so order those first.
my problem was a broken stud at the rear.
take out battery, power steering resovoir, bonnet alarm doodah. undo bastard bolt and take out dipstick tube. remove downpipe, drop oil and remove oil filter (makes it easier).
undo bolts, try to get the heatsheilds off but they are normally rusty. smash them off.
7 bolts on the manifold, three top ones from the top, front bottom one from the top with a "bent" spanner, rear three bottom ones from underneath. i used a 3/4 breaker bar and 6 point socket and got them all out easily.
good luck, its a "big" job, its gonna take you a good 10 hours working alone.
the stuff you need -
studs, nuts, manifold gasket, downpipe gasket, nuts/bolts to refit the middle 2nd to the 3rd section of exaust, new nuts for the downpipe.
iŽll get the part numbers in a sec, it all cost me 60 quid.