I did the job last weekend. Thanks for all the advice. It went reasonably well although it did take me most of the weekend. I couldn't get the lead to hug the tiles as much as I'd like but I can improve that later.
I'm please I went with the lead flashing and not the plastic bonding. It cost =A3130 in the end, which included about =A330 on tools so it worked out much cheaper than =A3350 too.
thanks Thomas