The job itself is not technically difficult - just requires watching what you're doing and making sure you get it all done right. Before you get started, check the head bolts you can see for paint marks - if you see marks, get a new set (they're only supposed to be used twice.)
You will want the engine DEAD COLD before you get started - let it sit for at least 24 hours. (I am assuming, of course, that you've done your checks and found out that the head gasket is the issue.)
Drain the oil and coolant. While that's happening, depressurise and disconnect the fuel rail from the supply/return lines, and unbolt the exhaust collector. Mark and remove all wiring that goes to the head, intake, and exhaust manifolds. Disconnect the throttle cable and tie it aside. Remove the EGR line (for RENIX) between the intake and exhaust manifolds.
Remove the valve cover. Mark the rocker arms for reassembly (they should go back in the EXACT SAME PLACE!) Find a way to sort the pushrods - same reason. Clean off the heads of the cylinder head bolts and look for paint marks - get new bolts if you find marks under there.
From the driver's side rear bolt, remove the bolts in an anticlockwise spiral (you should end with the passenger centre bolt) and lift the head and manifolds as an assembly (believe me, it's a lot easier this way.)
Put the head on a workbench (preferably a wooden surface) and clean the block deck. Rotate the pistons to TDC and clean the carbon off of them as well. Check the bores for scoring or other trouble.
Go to the head. Remove the manifolds and clean the gasket surface. Clean the cylinder head deck and the combustion chambers. Also clean the mating surfaces on the manifolds. Remove the EGR valve and clean the port, and reinstall with new gasket (if equipped - the bolts can be replaced with regular hex heads or socket head capscrews - they're a standard thread, and I just don't recall the size.) Might be a good idea to change the throttle bracket screws as well - but those EGR bolts are a B4$74RD to change with everything in place - putting a regular wrench to this is FAR easier! Use a thin layer of RTV Copper on both sides of the gasket to help prevent burnout.
Smear a light coat of RTV Copper on both sides of the manifold gasket, and install the manifolds. It is a good idea to use brass or silicon bronze bolts here, and retain them with LocTite 272. The brass bolts will want to be retorqued at about 2 weeks, but will hold well after that (mine have been doing well for about four years now.) Since brass is a little "springier" than steel, you will want to torque the bolts, then check them about an hour later - so take a break before you drop the head on.
While the bolts for the manifolds are setting, take a moment to clean the threads on the head bolts and check the bolts themselves. Make sure there are no thread deformations, and that everything is clean and not corroded. (The driver's side front bolt, for instance, threads into the water jacket...)
Get out some Copper never-seez and some Teflon pipe dope - you'll use the copper on all bolts but the one at the driver's front - THAT one gets the Teflon.
Working in a clockwise spiral from the passenge centre outwards, torque the bolts by stages to 25-50-100 foot-pounds (do each bolt to 25, then each to 50, then to 100) and touch-up the driver's side front bolt to 110 foot-pounds. Reinstall everything you took off before. Have a beer and pat yourself on the back.
Take a look at everything and you'll see why I told you to service the manifolds off the vehicle! Retorquing the bolts is a minor headache, but at least they'll already be in place and threaded - you're just checking that they're still tight.
5-90
Don't forget to paint the head bolts after you put them in - so you know for next time...