(sorry for late reply btw); the front bumper is straight forward to remove
remove the inner plastic guards in the front wheel arches (usually held on by plastic screws & grommets, or sometimes even zip ties here and there)
undo screws connecting the front bumper to the front guard (located in the wheel arch, sort of behind your headlights) i think there is two or three screws and a small bracket either side.
remove your front grill (just to get it out of the way) and reach behind your front bar, disconnect your indicators;
undo bolts connecting the reo bar to the chassis on either side;
front bumper and reo should slide straight out.
front bumper is then attached to reo with these plastic clamping brackets - be careful with these, easy to break (being 15 or so years old)!
i have a 94 GTST with the type M bumper. others may be a little different. but if you follow that guide, you should be able to work out any other little bits you might need to remove that i may have forgotten!
as for the 'hood'/bonnet, i haven't done it before, but i'm sure it couldn't be too hard.
i'd presume; disconnect water squirt hoses, undo bolts fastening the bonnet to hinges, bonnet off. replace with new bonnet, connect hoses (if applicable), and replace the latch (if applicable). might need to adjust it to make sure it sits flush etc.
good luck mate