When I was still living in Beirut, I regularly had lunch with my grandmother in her neighbourhood Thai restaurant. We never failed to order the pomelo salad for starters, a great favourite. Eventually the restaurant relocated and, for some reason, dropped the salad from their menu. My grandmother was still thinking longingly of it several years on, so I recreated it as far as I could remember, using ingredients easy to find locally. We were all delighted with it!
Skinning the pomelo is the laborious part, but the return is well-worth it. Any that is left over will keep a few days while getting even tastier as it marinates further. Make sure to return to room temperature before eating, to fully enjoy the flavours.
Note: Pomelos are far better known in Lebanon than they are in the UK, but they are readily available in London (look in street stalls, not supermarkets).