Used to work in Chiswick, but never got round to visiting the grave. I did, however, drag the wife and kids halfway across Zululand to visit Rorke's Drift 4 or 5 years ago. One thing they don't show in the movie is that it is on a piece of raised ground with a rocky ledge in front of it, which really helped the defenders.
no doubt previously spotted/posted but useful additional information here about Hitch and the other men : rorkesdriftvc.com - Pte. Frederick Hitch I'll be up at Kensal soon so will look out for Surgeon Reynolds' grave marker.