Hi,
When I lived in Florida, the best way we ever smoked oysters, clams & mussels was to get a nice fire going and get it down to a bed of nice coals. Put 2 or 3 cinder blocks stacked on top of each other in four corners around the fire forming a square or rectangle. Then, place either a large sheet of expanded steel or sheet metal on top of the four corners over the fire.
You can use a big piece of metal and a big fire too if you have a large crowd. Then, dump about 1 or 2 five-gallon buckets of wee-washed oysters or clams or mussels on the metal and spread across so there is only 1 layer. Then, to speed things up...place wet burlap sacks (save the ones your oysters come in for this) over the shellfish. When the shells pop open, they are done. If you like them more done, wait a little longer. Plus, keep some raw ones around because people love those too!! Some cocktail sauce, extra prepared horseradish, and melted butter and saltine crackers, and your favorite hot sauces are good to have on hand.
Oh yeah,....and LOTS OF BEER!!!!
I guess you could shell them first, but that is really a waste of time. Even restaurants steam them open whole.
note: the little pink crabs you occasionally find in the oyster are considered a delicasy!! They steam right along with the oyster and are like a miniature softshell crab about the size of a big M&M. LOL...really.
Man, I miss Florida now!!