I do clams and oysters on mine that I get off the beach....
I rinse them off, then just plop them on the grill, they steam in their own juice until they can take the heat no more, they POP open, often times shooting their wad completely out of their shell...
I grab them with my tongs and submerse them in different dipping sauce, barbque, garlic and butter, wasabi and soy sauce, etc....
Then shove them in my mouth.
Its soooooooooooooo good
BTW, shrimp are smaller, more to the pound, prawns here can be as big as 3 to the pound, hence the name prawns, NOT jumbo shrimp