First, take some tape and wrap it around each plug wire separatly, then label each wire according to the cylinder number. Use a spark plug socket and extention rod. Make sure your socket has the rubber gromett inside so it can pull the plugs out. Remove the front plugs and replace. Don't forget to put a little dielectric greast in the plug wire boot, this helps for later removal and keeping the connection clean. You might also use a little anti seise grease on the threads of the plugs as these are aluminum heads.
Next, you should really remove the coil packs unless you want your back to ache, your arm and nuckles to be scratched and you want to cuss alot. It is much easier if you do so. Now, if you can't slide the socket with the extension rod down together, drop the socket down there then slide in the rod and connect them in the "hole".
It is highly recommended to replace the plug wires at the same time. To do this remove one at a time and match the length with the new replacement wires. It is best on the Aurora engines to use AC Delco plugs. The engine is very tempermental with anything else. Also, use AC plug wires or another good wire. Don't go with el-cheapo's or you will get lots of stumbling with your engine.
Hope this helps!