I did mine last week, I'ts a fiddly job but the engine sounds sweet now. I needed to change the rocker gaskets as they were leaking anyway so it made sense to do the tapets and replace the plugs at the same time.
I made the special tool that's required to do the job out of a 10mm box spanner with a notch ground out to clear the high speed cam lobe.
For instructions there is a download on this site for "technical manuals" that explains what to do, it sounds more complicated than it actually is.
Good luck