I agree 18,19,21, 26 all great clues.
26a was the one that would have made me sputter my tea had I been drinking any at the time. Lovely!
2d deserves an honourable mention - just because it can work. Very elegant and amazing to me.
Well if you are planning your own funeral that is going to be full of pomp and ceremony and you have a wicked sense of humour then why not include a comedy element with a Land River hearse?! It was a relief to see a light hearted side to what is of course a sombre day for the Royal family and the nation.