There's a thread here http://www.landyzone.co.uk/lz/f8/bennehboys-d2-adventure-254514.html
where member Bennehboy does a load of engine work on his TD5. I haven't had the head off mine yet, so I don't know how hard it is, but is useful to see it all in pictures. Gives you a much better sense of the job than just looking at the manual.
Its not to hard a job. Just take your time and keep everything clean. Engine timing is critical so don't rush it. You are supposed to use new head bolts as they are degree torqued but I have reused them with no issues. Its your choice so if one breaks don't blame me.
If you don't remove the injectors or glows then don't put the head down flat or you'll damage the tips. Its a heavy old lump.
Give the inlet manifold a good clean inside while its off and get rid of the egr.