Clean the ribs, cutting off all the excess fat you can. There'll be a lot of it.
Place the ribs in a glass baking dish that will fit in your microwave oven. Typically, 3-5 ribs will fit in such a dish. Pour orange juice (no need for it to be good OJ---it's the acid that matters) to cover. Cover the dish with plastic wrap. Nuke for 7-1/2 minutes. Remove from oven, turn the ribs over (180 degrees) and nuke again for 7-1/2 minutes. The OJ will last two sets of ribs, then needs to be replaced.
Set grill to maximum temperature. Sear meat on one side for 1-2 minutes. Flip. Grill for 1-2 minutes to sear. Turn grill to low (about 350-400F). Paint tops with BBQ sauce. Grill for 5 minutes. Flip. Pait tops with BBQ sauce. Grill for 5 minutes. Serve.
About 2 ribs per person should do.